Father Material
by Animegirl257
Summary: Satan has never tried to grow or nurture anything in his life before, but for the sake of the only person who was ever precious to him, he's willing to try just once. In a bold move that no one could have predicted, Satan possesses the body of a stillborn Rin and does his very best to raise Yukio. He's actually quite good at it, demonic tendencies and hyper-possessiveness aside.
1. Smolder

Chapter 1: Smolder

 **My take on this "Rin is actually Satan" idea that was popular a while back. Except, this story will focus almost entirely on Satan growing up in Rin's body and only half trying to figure out how-to-human. I chose this point in life because it's clear that Rin was very affected by how people thought of him when he was young, while Satan almost surely wouldn't care. My interpretation of Satan is based on a little bit of what is seen in the early and late anime only, and drastic liberties have been taken to mesh the two. Hopefully it'll be understood with the emotional baggage of this first chapter.**

 **Don't expect a huge overarching plot, nor for this story to actually go anywhere significant. This is mostly a place to practice writing a little bit.**

* * *

" _You can't just buy or give life…but you can grow it."_

Why had Satan ever wanted such a thing? Why had such a thought ever filled him with a strange little fluttering warmth? He'd created children before, but it'd always been something that simple happened as a side effect and he hadn't really cared about. Yet the thought of _his and Yuri's children_ was…different. A unique feeling that he couldn't place but grew in time with the children (two of them, twins, he'd realized and felt nearly delirious) before bursting free when he first heard their tiny heartbeats.

The children themselves seemed like destiny and dreams brought to life. One, strong and housing the flames of the demon king in his heart, vicious nature sure to be balanced by the purity of Yuri's soul. The other was weak and squishy like most humans, but with just a tiny drop of demon in him that mad Satan excited. Neither would even fall in line with either demon or human, they would be outcasts for sure, but wasn't that all the better? They would become living impossibilities that would pave the way to Yuri's dream with their own surely immense power.

The two twins, hand in hand, would raze the very foundations of the exorcist's organization and overturn it all. No one would be able to stop them, because they were sure to be the best of both Yuri and Satan. Yuri's steel-clad kindness and understanding and ability to dream, Satan's raw power and fierce will, yes, they'd be something amazing…

Except…

The newborn was dead. Unbreathing, already cold and paling, the tiny child refused to move even as his twin wailed loudly. Not a hint of fire touched the empty shell.

Satan, formless once again, couldn't tear his eyes away from the lifeless child. Just before Yuri's labor, he'd been healthy and filled with such impossibly bright life, so why…?

" _Poor little one, it fell from the nest. It's already dead."_

A small herd of demons had helped Yuri through her labor, stolen blankets from the nearby lodge, and swaddled the newborns. When one had presented the dead child to him, Satan had stared, lost. A feeling of numbness had swallowed the rising bile fear for Yuri's life had brought, until the demon was unsure if he'd ever felt anything at all. Without the ability to form a thought, Satan had ordered the demon to give the corpse to Yuri, as if it could ever replace her (their?) precious child.

Yuri looked down to the crying child and let out a laugh that sent a shudder down Satan's spine at how _weak_ it was. "Ah…Yukio, there, there…it's…alright."

Yuri turned to the _dead_ child with unfocused eyes and slightly rustled the too-still, too-silent newborn, "You'd disturb your brother Rin." By some miracle Yukio quieted, slipping into a doze and Rin…Yuri blinked slowly, dazed and struggled to process what all the signs were telling her. But it must have resounded with her very being that something was very, very, wrong with her child, because in one moment the once unshakable woman grew very, very, afraid. "Rin?…Rin! Satan, Rin isn't…"

"He's a quite one, isn't he?" The words spilled from his mouth in a desperate tumble. Anything, anything to stop this! If he could keep Yuri happy, if he could keep her spirits high, then there was no way her soul would ever leave him, right? There was no way she, too, would… "You should enjoy the peace while it lasts. He's…He's a lot more like me than you, I can see it. He's going to be a little hellion one day! Just you wait…"

The words hurt to say. It went beyond any pain Satan had ever known, scratching angry red lines into his heart and bleeding out his sluggish soul. But the demon forced himself to talk, to comfort Yuri and assure her and even himself that all was right with the world. Yet, despite that urge, _need_ , Satan couldn't bring himself to finish his sentence.

" _You'll see what I mean someday_. _"_

Yuri's 'someday' would never exist. Satan could lie to her face about their children, but he could not lie to her about her own fate. They both knew it, dreaded it, and, while Satan raged against it and denied it, Yuri simple accept it with a gentle smile, content thinking both her children were alive.

Yuri looked towards Satan. She would never see him, and yet, every time she searched for even a moment she seemed to find his eyes. "Some would say I wasn't…the best child either. These children are...just as much mine as yours."

She would never fail to steal his heart a little more with every word she spoke. Satan wasn't to say something, to make a quip and joke and _pretend he was human_ , but fear and pain crushed he throat, stole his voice, and devoured his words.

Yuri smiled, sweet and filled with as much love as ever even as she laid there, _dying_. She, beautiful perfection that she was, sighed and sunk into an uneasy sleep where her life fell away like sand. She was slipping away and taking with her all the colors of his world. He wanted to embrace her and scream, rip apart the heavens and tear her soul free and bind it to him, chain it to himself forever and ever because she couldn't leave! He'd never felt love like this before, what it meant to feel light and filled with nervous happiness as the very worlds before him seemed to open into a bright infinity. Yet her soul, still bright and free of taint after the sin they'd committed together, still beyond his grasp, and he knew he'd never be able to hold it for himself when it finally fled her body. Why did his hands destroy everything…?

No. For once in his life, it wasn't _his_ fault.

Satan's gaze slowly fell towards the two infants in her arms, eyes sharp as an executioner's blade.

Overflowing from the deep well of his heart where new love had been once found, something black and thick tainted the spring. Light slid to shade and happiness became ugly rage he'd never known before. He'd been wronged before, by his own spawn before, but this was something beyond that. In one fell swoop, the two tiny creatures before him, one of whom was _dead_ , had taken the single most important thing in his life.

If only _those things_ had never existed, then Yuri wouldn't be doomed to die.

Satan reached, shapeless and formless as he was and the black hate twisted his heart and fanned the blue flames. A fire that Yuri had said warmed her very soul would soon once again only destroy when she finally drew her last breath, but that was fine. Yes, Satan was fine with that, because things would only go back to how they were, he would once again be alone like always. He was fine with that, because he could destroy the _thing_ that had taken away his only purpose. One of them was so weak it was already dead, ha! All he had to do was touch it, and the thing would die…

"This damn brat is…"

Weak, a nuisance, a _bane to his very existence_ , Satan had any number of words to describe the terrible creature before him who had the audacity to steal what was _his_ from him. All he could hear was white noise and he let himself become the demon he'd always been. Yuri had been nothing but a distraction from his true nature, his true calling of destruction and death-!

Instead, the word that escaped was a tiny whisper. A mere will-o-wisp among a ranging inferno, and yet the word burned into his heart deeper than any of the brands he'd intended.

"Yukio."

Satan drew away from the child, feeling very weak.

That was right…this…creature was still Yuri's precious child, Yukio. And he'd almost…!

Satan curled in on himself, nothing more than a wraith in this world, and hated himself deeply. Yuri….Yuri was too optimistic, too perfect, because he could never be anything good no matter how many times she told him otherwise. His own rage consumed him as easily as his flames did with all of creation, until he made mistakes he could never take back. So he would deny them till the worlds rotted together and not even the ashes of those mistakes would remain. It was simple, it worked, and it made it impossible to regret.

Except this time was different.

He didn't want to forget Yuri, he didn't want to forget the strange new feelings he'd experienced when he'd first learned they would have children together. What was he going to do with all them if left all alone? They'd surely sour inside his black heart, curdle into hard chunks and feel him up with even more bile than before. No, he, with or without Yuri, wanted to know more and follow the spider's thread to its end instead of sliding back into the life he'd known. A thread that was connected to the tiny bundle clutched tightly in Yuri's arms.

Yuri shuddered and, even unconscious as she was, clutched her children closer. Satan looked over the sleeping form of Yukio and felt his soul war with itself. The newborns were the bane and boon of his life, something he wanted to crush and destroy and yet couldn't because of how hard Yuri had fought for them. Satan couldn't understand the hideous chimera that his feelings were, so he decided he'd once again trust Yuri.

Yukio was something precious, something he'd love with all of his twisted heart. It would only be a fraction of the love he knew Yuri would have shown the child, but, after all he'd endured, he refused to let all they'd had end. Fate was terrible and cruel to the point where a mere moment of inattention had nearly destroyed everything. So he'd protect Yukio always, no matter where he went because the moment he wasn't there, somehow the world would find a way to kill Yuri's precious child.

It was madness, but Satan decided how he'd go about that sometime later.

Possessing the baby's corpse was easier than he'd thought.


	2. Preamble

Chapter 2: Preamble

 **Satan does not know how humans work.**

* * *

In hindsight, Satan realized he really hadn't made the best plan.

First and foremost: he'd made the mistake of assuming that the True Cross Order wouldn't send someone to find Yuri and finish the job as soon as possible. He thought he'd left their little shithole of an organization in a state of absolute chaos after the hell (ha!) he'd unleashed and that they'd be stuck scrubbing the bloodstains out of the walls for weeks. At least enough time for the demons he'd gathered under his natural thrall to whisk away him and Yukio to be cared for until he adjusted to his new body and could steal enough books on parenting to somehow figure out how to take care of a baby. The fact that he was technically a baby himself wasn't even a factor; he was the strongest demon in existence, he could handle anything!

Yet apparently the Exorcists had decided that the bloodstains and burn marks could wait until after they'd taken down the entire cause for the incident. Satan supposed it made sense to prioritize killing someone the devil favored over interior decorating. But he thought they had more common sense than that though: blood was an absolute _nightmare_ to get out if you waited until it dried. It was why he burned anything that got bloody, or dirty in general, and was in no way due to him being a pyromaniac. Just because he _liked_ watching things burn didn't mean he had a problem, and there wasn't anyone (left) alive who would (dare) say otherwise. His fire was pretty, who wouldn't want to watch it?

So when he'd heard enough gunshots and arias motor-mouthed to belong to an entire Exorcist squadron, Satan had panicked and decided that plans were for losers and leapt up and whisked Yukio off into the woods!

…Or would have, if he wasn't in an infant's body. It wasn't a matter of Satan's will not being strong enough, it was simple physically impossible for him to move. Or speak. Or even make sounds beyond some gurgle-spiting noise that left Satan disgusted with himself. So Satan admitted that, when it came to making plans, he left something to be desired. Like the simple knowledge that yes, a newborn was exactly as squishy as it looked and had the approximate muscular build of a vaguely human-shaped marshmallow.

That still didn't mean he could set literally everything that wasn't Yuri or Yukio on fire if need be.

It turned out that the bastard who'd arrested Yuri, Shiro, was actually quite soft. Satan had smiled when the man had begun to draw his sword, for deep within the demon a tight ball of all-consuming fire roared, growing stronger by the second and ready to burst free. He'd turn the man to ash in seconds, and if Samael was too slow to get out of the way in time, well, that wasn't Satan's problem. Except the sword was abruptly sheathed and the resolve drained from Shiro.

The flames buried in Satan's chest sputtered and died to a dull flicker the longer the conversation went on. So even Samael had no idea what had truly happened?

Interesting.


	3. Line of Sight

Chapter 3: Line of Sight

 **Satan's daily lessons in the art of badassery begin. Kind of.**

* * *

At barely five years old, Yukio learned what it was like to fear death.

Eyes filled with hate glared at Yukio, pinning him under an intense gaze that threatened to choke him. Lips were slightly pulled back to reveal the tips of too-sharp teeth, and added a certain feralness and unpredictability that was a horrifying combination. Yukio couldn't even make himself look away, terrified for his life to lose sight of the one looming over him for even a second. If he dared to look away, surely the _beast_ before him would take advantage of the weakness and tear him apart.

And then the terrible look fell away within a second, slipping off like water and leaving not a trace behind. Yukio sighed in relief as his brother Rin returned to him, and not…whatever that had been. Voice still a little weak, he asked, "How you can make yourself so scary looking?"

Satan thought for a second and realized he didn't really know. It was just something that came naturally to him, so maybe the truth was the best answer: "Thousands of years of practice."

"But Rin, you're only as old as I am!"

Physical body wise at least, Satan thought flippantly, but there was still another important thing Yukio had left out; "You forget, _I'm_ older by a couple minutes!" Yukio grumbled at Satan's cheeky grin, turning away with clear frustration and already ready to drop the subject out of spite. Knowing short attention spans intimately, Satan took pity on the boy, "Fine, fine, you do it like this. Look at me." A nod. "Now pretend I'm someone you _really_ hate."

"But I don't hate anyone!"

"What about those bullies at school?"

The silence was deafening. Or it would have been if Satan hadn't groaned loudly a second into it, rocking back on his heels and palming his face.

"Yukio…" Satan shook his head, disappointed and fixed the boy with his most serious stare that wouldn't cause outright terror, "You have to stand up for yourself!"

"But I don't want to fight them like you-ah, I mean…"

And there was the crux of the problem. Normally, such passivism would have thrown Satan into a rage, but he could see traces of beautiful Yuri in Yukio growing every day. To solve things between humans and demons without violence, to have the will to not fall into hate, surely he was already seeing traces of that in his son. He just lacked the confidence in himself to form true resolve, and Satan wouldn't rest until he'd built Yukio's confidence until it at least matched Yuri's. Maybe even higher, if such a thing was possible. Small obstacles like the idiots at school would just be the first and hardest hurdle. From there, it'd be easy.

"It's fine, you don't have to fight anyone." In the future there was no way Satan _wouldn't_ be changing his stance on that, but it wasn't as if Yukio even could just yet. Satan personally considered himself pretty awesome, and even he was only just getting a hang of his weak and clumsy body. He couldn't even properly break an arm anymore, and he'd tried really hard to do so in that one fight! Honestly, he was seriously disappointed in himself and had already started working out, ignoring the way it baffled the priests.

"But you have to stand up for yourself eventually, or I'll do it for you." Again, however many times it took for those idiots to get the message beaten into their skull. Or arms. He wouldn't mind getting a chance to try again in a few weeks after he'd built his muscle mass up. Did they think they won just because the teacher only ever seemed to get mad at him? Like he cared what that bitch said to him if she was so blind she couldn't even see the disastrous state her classroom was in just because a few snot-nosed brats could cry on will.

"Just make them think that messing with you isn't worth it." It was something Satan had done with the demons in the town, letting just enough of his aura out to keep most away without them even knowing what they were avoiding. Anything more dangerous and a tad smarter that wandered in he'd let the Paladin be useful for once and exterminate. But humans were a bit too dense to get a clue, sadly. "And if that doesn't work, well, I'll handle it."

"You don't have to…"

"Of course I do! It's my job to protect you!" From bullies, from demons, from the entire world if need be. He'd burn it all like his own dreams, his very life, had been if it came down to it. Nothing, not the entire army of exorcists, however few remained after his handiwork, would stop him from giving Yukio the life Yuri would have wished for him-!

Satan pushed the darkness that felt suspiciously like madness away, drowning it with Yukio's (Yuri's child, Yuri's precious gift to him) presence and a long-suffering sigh, "Come on, your turn! Give me a good glare, one that'll make those idiots piss themselves!"

Yukio grimaced at the language, knowing it was bad from how mad it made his dad. But that was just one of those things Rin would never ever budge on, no matter how much he was scolded, and he was almost as bad about it as he was about insisting on defending Yukio. He'd just accept it as one of the strange things about his brother, no matter how much he hated it, and move on.

Yukio breathed in deeply and did his best to picture the terrifying face Rin had shown him. Not that he'd ever forget it, but he'd do better if the image was in his mind as he tried to recreate it- just like he did when learning letters. Rin was really good at that and could even already read really well, so maybe that was the key. He imagined the face he'd show his big brother, terrible and so scary it'd even make him flinch back.

Goal in mind, Yukio glared at Rin.

A moment passed.

Satan burst out laughing.

"Rin!"

"You look like you're taking a shit!" He shouted between gasping cackles.

It wasn't a shout but an embarrassed whine of "Rin!" that made Satan laugh even harder. It took a solid minute for the demon to calm down, and by then Yukio was thoroughly red-faced and pouting.

"And now you just look like an angry kitten! Come here!" Yukio refused to move, but that was fine, Satan just physically pulled him closer until his son was practically in his lab. Maybe the pats to his head would have been comforting if Satan had been able to control his giggles, "You are just too adorable; I didn't know humans got so red!"

"'m not abdoro….adorable."

Satan chuckled at his precious struggling with even such a basic word. Everything he did…"Sure you aren't."

Yukio whined and tried to hide his face. It did nothing to stop Satan from fawning over him.

Shiro walked in, took stock of the state Yukio was in, and raised a brow, "What's all the noise about? What's wrong with Yukio?"

Yukio was so much like Yuri when she got frustrated with him, with reddened cheeks puffed in frustration and eyes that refused to look anywhere but straight ahead. "He's being perfect. My adorable lil'..."

Whatever was said trailed off into unintelligible cooings. And Shiro could only sigh with amusement at the entire thing. But Yukio looked as if he were about to explode from embarrassment, so it was his obligation to save him, "Rin, don't tease your brother too much."

"I'll do whatever I damn well please!"

"Language."

"Be something more than a piece of shit priest first!" Honestly, how dense was this man to not even realize what he was willingly housing?

"Language, Rin! You'll be a bad influence on Yukio at this rate!"

"Yukio is too perfect for that to ever happen. You know not to say the things I do, right? Well, at least not when the shitty priest is around…"

The back-and-forth was practically automatic, well-rehearsed and recited to the point Shiro had already almost given up hope on restraining Rin's vocabulary. Or controlling the child in any meaningful way at all. If he was this bad as a little kid, Shiro shuddered at the thought of an even more rebellious teen to deal with. But he could handle it. He'd beaten back Satan when he'd possessed Yuri's body and tried to attack him, so surely Rin couldn't possibly be worse?

"Why are you still here? Go cook lunch already!"

Shiro sighed, exasperated. At least Yukio was sure to be a good child, Rin would just…require work. Work and trial and error to figure out how to appease the demonic tendencies that slipped through the seals. Theoretically, demons should have had a high respect for hierarchy…"Rin, I am the adult here."

"Riiight."

…But Rin was an alpha male if he'd ever seen one. So, something else then, possibly…?

Satan waved away the shitty priest, deciding his presence was slowly ruining his good mood. "Then be an 'adult' and go make food. Unless you think we should be around the stove?"

The worst part was, Shiro couldn't even technically argue against that.


	4. Take Notice Not

Chapter 4: Take Notice Not

 **Satan thinks demons are as annoying as school. Other demons, not him. Because he's better than them.**

* * *

School was a drag. It was nothing but hours of Satan's day involving being talked down to by some idiot teacher and forced to listen to lessons about basic shit he already knew. Sure, he couldn't expect much out of his first years of "education" (a word he used _very_ lightly), but he just wished that the moron heading the class would leave him alone since he clearly knew everything she wanted to teach. He'd participate whenever he damn well pleased, he'd talk whenever the hell he wanted, and he'd use whatever fucking shitty words he wanted, capiche bitch?

Apparently not, since that got him sent to the office, and, when that did nothing, calls to the shitty priest. Which did even less, but it seemed to broadcast to the other kids that he was fair game to pick on since the teacher hated him. Not that Satan was ever "picked on" by anyone, no, or more amounted to dumb words said by dumb children who eventually got sick of and punched in the face. It was something Yukio didn't like, tried to stop, and often got caught in the crossfire, being the easier target who'd actually cry when teased.

Satan just beat those brats even harder.

Of course, he'd found a more…permanent solution was needed. So, with a tiny flicker of his pretty blue flames, he burned a Temptaint into a few of the kids and let them deal with the trauma of suddenly seeing demons everywhere. It helped that Satan could attract lesser demons at will, letting them mindlessly swarm him and terrifying the brats until one literally pissed themselves. Suddenly their class was a whole lot smaller, several children out "sick" as the teacher phrased it when asked. She sure had a strange way of phrasing a sudden case of what the rest of the world would perceive as insanity, but whatever helped her sleep at night. And when the shitty priest asked about it, Satan played dumb, pretending he'd simple fought them like normal and they'd suddenly started screaming. For no reason at all, as far as he could tell.

It was kind of funny that the idiot thought it was all unintentional. Of course, the best, the strongest, lies were the ones someone said to themselves.

Suddenly, Yukio had stopped mid-step, and stared at a car. No, not at it, but under it, where Satan saw the edge of something scaly disappear, practically merging with the shadows. A minor taint filled the air, and Satan sighed, annoyed that a demon, however minor, had gotten close. He'd have pretended it never happened, expect he saw the way Yukio's eyes filled with nervous fear, refusing to leave the spot.

"Annoying, aren't they?" Satan said casually, as if it were simple the weather and not beings from a whole different world. Which to him, it might as well be. "Just ignore them and they'll go away."

Yukio nodded, slowly, "I…know that."

"Yukio, we've talked about this before." Years ago, when the boy was barely three, and had first spotted one outside the church and screamed. The coal tars had never really bothered him, simple a fact of life, so Satan had been surprised and forced to literally drag Yukio to the side and have a nice long talk and establish ground rules for demons.

" _You can see it…?_

" _Of course. Everyone else is just too dumb to see them. But not us."_

It'd been obvious that he'd gotten to talk to Yukio about it all before Shiro, and that filled him with vindictive pride. There was no way the shitty priest didn't know at least Yukio could see demons, but with how much of a non-issue such minor demons were to himself, the ruler of Gehenna was wondering how long he could keep the Paladin from guessing he could see as well. It was funny to see him tip-toe around the issue with his two so-called sons (the deluded fool), probably wanting to "maintain their innocence" or some other crap for so long as it wasn't an issue. All thanks to Satan actually _telling_ Yukio what was going on

"But…"

Yukio was still unsure, so Satan decided to remind him of the basic rules, "They won't bother you if you ignore them, Yukio. It's only when they see you scared and know that _you_ can see them that they'll do anything at all." Not that he'd ever let that happen. They could try, and he'd destroy them.

Yukio nodded, repeating those words to himself as Satan gently led him away by the hand. "I just wish dad could…"

Ah, one of Satan's finer achievements in his new life: convincing Yukio the _goddamn Paladin_ couldn't see demons. It was hilariously ironic and meant his child would come only to _him_ whenever demons gave him any issues. Good. "Well, he can't, so we shouldn't bother him about it. Wouldn't want him to think we're like those other kids, right?"

Even if it'd never been his intent to use those brats as examples, he'd gladly take the chance he'd made. Yukio nodded furiously and Satan, unseen, smiled happily, and tightened his grip on Yukio's tiny hand.

Yukio squeezed back, and looked up at Satan with gratitude.


	5. Snowfall (1)

Chapter 5: Snowfall

 **Broken up into two parts to keep the chapters at a slightly more consistent length.**

* * *

In Satan's honest opinion, Assiah was nothing short of amazing, and he'd gladly admit it if asked. There was a whole lot more to do, a whole lot more to see, and he was slowly but surely developing a soft spot for the overly bright world. He didn't have as much freedom, but no one knew about him so idiots who were full of false bluster foolishly challenged him. Some people might have found the fights annoying, but it was the highlight of Satan's day, getting to beat the crap out of a few kids, shattering their hopes of grandeur at their feet as the 'little kid' utterly destroyed them. It was vicious and difficult sometimes with the bigger kids, but Satan liked the burning of his arms, the stinging of cuts and scrapes, and tangy flavor of mixed blood in his mouth. He welcomed the pain he hadn't felt in years, had forgotten existed, and would always walk away with a dopey smile feeling thoroughly satisfied with himself despite knowing how petty these fights actually were. They made him feel alive in a way that reminded him fondly of his very early days when he'd carved his way to the top, bodies his stepping stones and blood his drink. Yes, maybe Assiah wasn't that bad after all. It sure explained why his other sons kept going to such an otherwise overly flammable world.

The cold, however, could go burn in hell.

Once upon a time, he hadn't cared if it'd been scorching hot or a blizzard outside. Whatever bodies he found barely lasted long enough to be affected by the weather, and even then his power warded off the cold effortlessly. But robbed of most of his inner fire by the shitty priest, Satan had no defense except the shoddy human clothes bought for him. It made him shiver, locked his joints with ice as his blood slushed through his frosted muscles. He felt terrible whenever winter rolled around, and no amount of layers could ever seem to fix the issue. So Satan simply pretended the outside world didn't exist whenever that wretched white stuff that was nothing but glorified ice fell, and curled up in front of the space heater like a cat. And he'd be content to stay there for days at a time, except-

"Rin! Rin! Look, it's snowing! It's snowing, Rin!"

For some reason he couldn't fathom, Yukio loved the stuff.

He supposed it wasn't _that_ bad. He could look at the dusted trees and, for just a second, pretend he were in a familiar forest. Reality would fall away and he'd pretend he was hiding in the lodge, overly grumpy and stubborn just to make Yuri work to force him out with sighs and fond grumbles. She'd have dragged him out, but her hands were busy holding and guiding their two-

Shiro's voice filtered down the hall, "Rin, hurry up or we'll start without you!"

"Don't you fucking dare!" Satan forced his other boot on and checked it was tight and secured. He hated when snow got in and sent shivers up his spine.

Satan nearly tripped down the steps when Shiro pulled on his scarf and turned him around. He wasn't even entirely sure there was a child under all the fluff, "Rin, just how many layers do you have on?"

"Not enough."

Shiro laughed and practically shoved him outside.

It turned out that Yukio was impatient and was already crouching in the light dusting of snow, rolling a tight snowball and trying to get it to pick up the white flakes around. Satan joined the boy, ignoring the stabbing cold, and flung snow onto the ball. There wasn't much snowfall in general, but the yard in surrounding the church was big and spacious and thoroughly covered. Shiro trailed after them, a faint voice offering to help push that was ignored even as the snowball grew into a boulder that nearly reach Satan's shoulder. Unbothered, he dug his heels in and pushed what had to be well over a hundred pounds of compact snow towards the entrance of the church while Yukio ran off excitedly to start the second ball. He left it closer to the road than the church, just barely kissing the barrier, and nodded at the arbitrary placement as if it meant something.

Across the street he could see a few demons drifting listless about, searching for bodies. They were nothing more than formless wraths, but he recognized a few demons that enjoyed possessing snow-structures. One of them broke from the group, falling behind as it stared vaguely at the snowball he'd just shoved into place. There was still the barrier in place, but it naturally wavered and weakened whenever Satan stood too close for too long, confused as to exactly what he was.

"Rin! Rin, we finished the body!"

A quick glance back and Satan saw Yukio happily leading the priest, who was pushing a lumpy snowball only a bit smaller than the one in front of Satan, towards him. He felt the other minor demon draw closer and, without a second thought, snapped towards it and snarled. The demon recoiled and, like the weakling it was, fled. The ruler of Gehenna nodded, quickly scanned for any other curious demons unearthed by the snow, and, satisfied, turned back towards the approaching duo.

But there was yet another problem, "That's too big, it won't fit on top." Also Satan couldn't deadlift that much weight just yet and like hell the shitty priest was going to be the one to make the snowman.

"It got bigger on the way here…" Yukio muttered with wide eyes, as if he'd just seen something impossible and not simple physics, " _very_ bigger." He held his arms wide for emphasis.

"Much bigger." Satan and Shiro corrected in unison without a thought. He ignored the annoyance he felt, and turned on the priest, "Should have carried it."

Shiro blankly looked down at the compact snow at his feet, "Do you have any idea how much this thing weighs?"

"Less than a hundred; you should've been fine." Sure, humans were pretty weak, but this was the _Paladin_. He brushed off the shitty priest's comment of "try two hundred", because the principle was still the same, "Unless you're letting yourself go. Come on, Yukio!"

Without any ceremony, Satan violently kicked the snowball and cackled at the explosion of white. Shiro stumbled as the mass rocked enough to nearly topple him, and he gave Satan a rather pathetic stink-eye. Yukio sputtered as some of the impromptu snow shower hit him, but shook the powder out of his hair and, after a moment where in which Satan had to encourage him, kicked the snowball with all of his seven year old might. The boy gasped when he foot skidded off, and stumbled, slipped, then fell. Or would have, if Satan hadn't seen the result of such a disastrous stance a mile away and was already behind Yukio, supporting him.

"Careful! I'm glad you're so enthusiastic, but you can't just kick without bracing for recoil!"

Slowly, Satan went over the steps to what he deemed a proper kick, making sure to spell out in excruciating detail the importance of ever little body movement. His natural grace, however, outstripped a human's on his worst days and Yukio, sadly, already had a terrible habit of overextending. It was adorable the way Yukio stumbled and grew frustrated with himself, unable to pull his leg up properly or figure out how to 'snap' his foot forward, cheeks even redder than they had been when the cold nipped at them. Comforting him only made it worse, and Satan was too busy fawning over his child to notice the bizarre look Shiro was giving him.

"Rin, where did you learn that?"

Oh right, the shitty priest was here, and Satan supposed it was really weird to see a child who knew so much about the technicalities of actual fighting. Whatever he'd seen in the past had just been Satan beating a few fools who he didn't actually _need_ to try against, even if they were older kids. And while his prefer style was an all-out offense with claws and teeth, at some point or another he'd had to refine things to at least some extent.

"Practice." Shiro looked unconvinced, so Satan decided he'd humor him at least a bit, "I fight a lot cause it's fun. Someone's shitty older brother offered to teach me a little bit."

A blatant he hadn't thought about in the least, but already, as naturally as breathing, the threads spun free, "He didn't like that his younger brother was such a goddamn baby, so he's taught me a bit."

Shiro nodded, accepting the explanation and crouching to pile up the snow Yukio was enthusiastically kicking away into a third ball. But the look in his eyes set Satan instantly on guard. It was doubt, not of his story, but of the person who didn't exist. "Alright, well, I'd like to meet him sometime then."

"Can't. I see why his little brother doesn't like him. He was an ass who didn't like it when I actually won. Which was all the time, by the way." Satan explained, discarding his imaginary teacher at even the slightest hint that a flaw could be found. As if he were so dumb as to let such a small lie go on for too long.

"Language. And that's a shame, but," And here Shiro raised his voice a little, making sure Yukio heard, "if someone ever makes you feel really uncomfortable or, lord forbid, unsafe, then you shouldn't hesitate to get away from them and come to me."

Not exactly a bad lesson to try and teach, but Satan, fundamentally, couldn't let the man have anything, "My fatass teacher makes me feel uncomfortable with how dumb she is. Can I stop going to class now?"

"That's not what I meant, Rin, and you know it. Also-"

"Language, I fucking get it. And also don't oversimplify things." Or people like him would pick his words apart and throw them right back with sharper edges that cut away plans, "That's enough, Yukio."

"Oh, ok."

It was simple to pick up the snowball now that it'd been halved in size. Yukio 'helped', desperately pushing as Satan bore the weight, cheeks puffed out as he gave it his all. He let just enough weight bear down on the little boy to make him feel useful and slowly guided the ball on top with a solid thump. It rocked shakily and almost immediately Yukio was shoving snow in the seam to try and steady it. They spent a few minutes smoothing the two lumps into something vaguely resembling a torso, Satan more or less guided by Yukio's whims to make the "most perfect snowman ever", brushing a little bit of snow off here only to add it back a couple of inches over, standing on the tips of his toes to pat down the top.

When Shiro finished his own personal project and lugged what hat to be the head over, Satan intercepted him and snatched the ball out of his hands with a flat glare. Instead of being annoyed, however, the shitty priest only looked smug and shrugged, "Go ahead, Rin."

Satan was suspicious until he turned around…and realized the snowman was a good deal taller than him. Tall enough, in fact, that he couldn't properly reach the very top even when he stretched as far as he could.

Yukio watched, wide-eyed and worried his twin would topple the whole thing over, "Be careful!"

"I…am! Son of a…!"

Shiro, still looking amused, coughed loudly to cover the curse (as if it made a difference), and asked, "Do you want me to…?"

"I've got this." Probably. If he stood on the tips of his toes and stretched, then he'd be just tall enough to place the head.

Probably.

He'd beaten worse 'probablies' before.

Probably.

And so Satan, trapped in the body barely past its toddler years, stretched with all his might. He felt the snowball rest against the torso and tried to push it forward. But the slope was still pretty sharp, and he very nearly lost it several times, snow threatening to slip free from his fingers. But he was so close, almost there, and-

He fell face first into the snow.

The snowball fell on top of him and exploded.

Shiro snickered, even as Yukio shrieked with worry and desperately set out to 'unearth' his brother.

Satan just groaned.

* * *

A resolution was reached between devil and priest, and Yukio, sitting on Satan's shoulders, placed the newly constructed snowman head on top, guided carefully by Shiro. By that point Satan had started to feel quite cold and miserable and simple grit his teeth to stop the chattering as he helped Yukio dress up the snowman. When they were done, scarf, sticks, and stones in place, Satan sighed happily, readily to head to the _warm_ indoors.

Or at least he was, until Yukio suddenly seemed to be struck by an idea and ran away. A moment later he was on his knees, gathering and patting down snow once again, "Rin! Rin, let's make another!"

"But Yukio…there isn't enough snow to make another." Really, there was, but Satan just wanted to go inside already.

"Um…We'll make a lot of littler ones then! A…A snowman army!"

Either the shitty priest was also getting cold or had noticed the now shivering boy's distress, and loudly clapped his hands to get Yukio's attention.

"Alright, who wants hot chocolate?"

Yukio perked up, snowman army goal suddenly forgotten, "Marshmallows?"

Because that was all the boy really cared about, since Shiro only ever used the grossly oversized ones that Yukio happily picked out at the store. Satan found it adorable how Yukio would play with them as he slipped the boy his own balls of puffy sugar and then sipped his (marshmallow free) hot chocolate.

"Of course! You can even make a marshmallow snowman." Which was sure to be messy, Shiro rationalized the sticky hands would be cleaned with a hot bath.

Satan smile, deciding that, while he still very much hated the cold, he could tolerate it once in a while for Yukio's sake. Especially with the promise of hots drinks and a warm space heater to camp near. Maybe he'd figure out a way to coax Yukio into making an even bigger mess than normal just to give that shitty priest some more work. Yes, that'd make the day even better.

But of course the power had to have gone out at some point while they were outside.


	6. Frozen Over (2)

Chapter 6: Frozen Over

 **Continuation of "Snowfall"**

* * *

Satan huddled in as tight of a ball as possible, verbally cursing the _cold_ world and mentally compiling a hit list of incompetent people. The idiots who'd somehow let the power go out were right at the very tippy top, only slightly below the architect who never thought to install a real fireplace here. The other Exorcists who loitered about the church were carefully tiptoeing around him, nervous by easily the worst mood they'd ever seen him in. Well, at least they were less mouthy now, silently trying to figure out a way to appease him before something terrible happened.

Yukio wavered a bit, unused to seeing his strong older brother in such a…sad state. Sure it was cold inside, but it wasn't like it was as cold as it was outside! "Rin…the power will come on again soon!"

Satan grunted in vague acknowledgement, but otherwise ignored the still-chipper Yukio, who started babbling happily about their time outside as if it hadn't just happened. Shiro was on the phone with someone or another, and Satan eyed him suspiciously, almost certain the shitty priest was trying to pull strings to get the power back on early, lest the 'spawn of Satan' grow uncontrollable. Honestly, what did that shitty priest thing was going to happen? That he was going to set the house on fire for warmth? Granted, he _would_ be warm then, but where was he going to sleep after that?! Seriously, he wasn't an utter moron like-

Wait.

"Yukio, come with me."

"And our snowman is the bestest and…Oh, ok, Rin."

"Yes, it is the _best_. Now come on!"

* * *

Shiro didn't notice the boys leaving the room, or else he would have done something. He'd been busy on the phone trying to pressure Mephisto into sending over a battery powered heater or something. Honestly, he really didn't care whatever contraption the borderline madman sent his way, just so long as he got a heat source soon. Except the man was being absolutely impossible as usually, laughing off Shiro's worries. Rin's foul mood was practically palatable to the point that Shiro was quickly becoming afraid of what the boy would do-

The smell of smoke was a slap in the face.

"Rin, the tree! You're burning the tree!"

Shiro was frozen just long enough to feel both his heart and phone drop to the floor. Not that he even noticed, already shoving through the door and nearly breaking it off its hinges and praying he wasn't too late. Somehow, in what had to have been ten minutes at _best_ , Rin had drug an old broken pew no one had gotten around to taking to the dump into the yard…and had set it on fire.

Of course.

The old wood, dry and brittle (like his sanity, Shiro thought cynically) had erupted into an impressive blaze the boys stood rather worryingly close to, Rin looking pleased with himself. Thankfully, it was the middle of the yard, far away from any trees or buildings. In one hand he held an old Christmas decoration, a miniature stuffed tree, which was also on fire, because of course it was. He poked it with a twig and stirred up the cotton inside it, watching it blacken and turn to ash without fear, even as the flames licked closer and closer to his hands. Yukio stared, fascinated as the bright colors turned black when swallowed reds and yellows, a strange contradiction in his mind. He clutched yet another plush tree to his chest like a teddy bear, not sure if he should be afraid or dazzled by the sight before him. Rin made motions to set that 'tree' alight as well, though Yukio shrunk back, clutching his new soft toy possessively.

"Rin, please stop trying to turn your brother into a pyromaniac." Shiro sounded dead inside even to his own ears, because maybe he was just in a tiny bit of denial that Rin had started methodically burning a box of Christmas decorations over a flaming pew like a tiny anti-Christ in the making.

Blue eyes flickered to the Paladin with clear disgust, "I'm not a pyromaniac."

Shiro looked at the burning pew and collection of sticks and decorations piled around it. He'd question the 'how' later, after he'd thoroughly searched the twin's rooms for any matches he was now sure Rin had squirreled away.

Satan noticed the shitty priest's eyes flicker to the fire and shrugged. To him it was simple logic, "So? It was cold."

"Rin, you just set something on fire." Somehow. At least it was normal fire and not blue, though the consolation was tiny and hardly comforting. "What am I supposed to think?"

"I think you should think that it was fucking cold."

Shiro sighed and slowly repeated as many prayers as he could remember to shave off the rising irritation. He was calm, he was centered and perfectly in control of his life, and not at all rapidly reaching the end of his rope with one of his beloved children. No, he _would_ be the pillar to ground Rin's wild behavior, even if it killed him. But first, he had to do something about the burning pile of wood before someone called the police.

At least he would have, if Rin hadn't firmly placed himself between him and the fire, looking incredibly unamused as if Shiro were the child, "No. This, all of it, is mine. At least until you do something about the damn power."

"Rin, fire is dangerous."

"If you're fucking dumb, maybe. So I guess you should stay the hell away before you get burned."

He ignored the insult to his intelligence and gratefully took the fire extinguisher one of the Exorcists had had the foresight to bring out as they chased after him. At least they hadn't literally jumped the gun and started shooting, though he caught sight of some twitchy fingers, "Rin, I'm putting the fire out. Now."

"No you aren't."

"Rin-!"

"Shitty priest! See, I can say names too."

And like that it continued for some time until he was borderline shouting, with Rin looking nothing but smug as he riled the man up effortlessly. Shiro hated this, the arguing, but Rin was unmovable and unshakable, with enough raw power and talent to potentially seriously hurt both himself and even Shiro if it came down to blows. If he couldn't ever get the boy to yield to him even once when he was this young, then what hope did he have to control him if when he grew older, stronger? What would happen to Rin if he ever awakened his powers if he was already this vicious? Why couldn't Yukio have been the one who had inherited the powers? Then at least he wouldn't have to seriously considering the idea that someday he might have to put down one of his children (they were _his_ now, no one would ever tell him otherwise) like a rabid animal. If Rin could never take an order, never listened to anyone, then how would he ever convince anyone he wasn't a serious threat? How was he supposed to-!?

"Why can't you just _listen_ to me?"

"Why should I?"

"Because I am your _father_!" Because he was sure to be the only thing between Rin and a violent execution one day, but only if he could make it seem as if the boy wasn't a demon in heart and mind. How was he supposed to do that when all Rin did was _act like a demon?_

Satan, however, didn't at all like it when the _filthy beast_ before him pretended to be Yukio's father. He only accepted it as a necessary evil for easy access to Assian goods and luxuries, but to hear it shouted in his face, as if the filth understood anything? Unacceptable, and the ruler of Gehenna let venom spill from his lips. "No."

Shiro recoiled as if slapped, reeling and gaping as if he were sucking in air to fill the hole suddenly torn in his heart. It took too long to answer, and he stared in horror even as Rin was unmoving, "…What?"

"You aren't anyone's father. Not mine, not Yukio's, so _shut your fucking mouth_."

It was so simple, so easy to utterly destroy the Paladin that it was pathetic. Before his very eyes, he saw the man crumble, unable to accept the words and looking as if his world was crumbling. Good. Satan couldn't care less about how much he hurt the man, for a thousand lashes to his soul would only be a miniscule fraction of punishment due. This was _nothing_ compared to what he'd done when he'd ripped Yuri away, and Satan would gleefully force him to suffer and struggle with a hopeless battle to make one of his 'adopted children' love him he'd never win.

And when Satan was satisfied with his strength, he'd finally kill that man and-

"Dad is my dad!"

The shout was powerful, shaking with its raw emotion laid bare, and for a moment Satan didn't recognize his son's own pained screech. Locked up, he turned and saw the boy, fat tears pooling in his eyes and suddenly the demon remembered that Yukio had always been there, listening. He'd been so mad he'd forgotten, said things that there was no way Yukio would understand, and the poisonous emotions he'd felt evaporated…He had to fix this, stop it before-

"Dad is my dad, and I love him! Rin is my big brother, and I love you too! So why can't…why are you two always…" Yukio broke down into sobs, trying to hide himself behind patterned mittens.

Distantly, as if there were a mile between them, Satan heard the shitty priest start talking, trying to comfort and sooth. He ignored the man, ignored the disgust he felt that the Paladin was even near his son, and stumbled to Yukio's side, reaching to embrace him like he'd done so many times before. Except…

"Don't touch me! Why can't you just love dad like I do?"

"Yukio…!" And then Satan was falling, pushed.

Yukio's shove knocked Satan into the snow, and the demon let himself fall, too stunned to resist. Any happiness he might have felt at the display of strength withered and died with the sound of Yukio's sniffle sight of red eyes. "Why do you two hate each other? I hate it!"

"I hate you!"

Yukio ran inside in tears, slipping past Shiro without slowing even when he cried for the boy to stop, his brother hot on his heels even knowing he'd be pushed away. The priest watched the boys run inside, feeling oddly disconnected from everything that had just happened. He could feel the divide between him and Rin, a gaping maw he just couldn't pass, and, with practice, steeled his heart for the difficult days to come. He managed to put out the fire without issue and, after the last of the flames were gone, realized something.

Rin was right: it really was cold outside and the faint wisps of smoke couldn't hope to fill his heart.


	7. Tinder and Flame

Chapter 7: Tinder and Flame

 **Expect as many tone shifts as people Satan has set on fire.**

* * *

It took Satan approximately seven years of his new life to meet his first true threat to Yukio.

Oh sure, he hated the shitty priest on a fundamental level, but the man was at least determined to protect Yukio and too stupid to see who Satan actually was, so the Paladin got a begrudging pass. There'd been other annoyances over the years, but they'd been nothing more than petty bullies who wouldn't actually seriously hurt Yukio even if they had the chance to. Not that Satan would let even that minor of a threat stand, mind you. They were lucky his fire was mostly sealed or he'd have branded that lesson into them more than he had. Demons were even less of a problem and instinctively fled from him, and by proxy Yukio, without knowing why. Any that got too curious he destroyed.

But this threat was...

Unexpected.

The woman looked nice enough. She was pretty, with a face that was attractive enough to be considered desirable, but not so perfect as to be unapproachable. A softness graced her limbs in all the right places, making her look gentle and loving, while still beautifully curvy. Overall, the ideal of a young mother.

Satan also knew she wasn't that boy's mother.

Hand in hand, the young raven- haired boy Satan vaguely recognized from class hummed happily as he skipped away with the stranger. The boy, whose name Satan hadn't bothered to remember, was someone in his class who had something or other messed up in his head that made him _too_ nice. He would walk up to anyone and everyone and casually declare his love for them and would beg to play or for attention in general. There was nothing terribly wrong with him, but the general over affection grated Satan's nerves. However, Yukio liked him and the two got along, so Satan would tolerate the boy.

Weak demons swarmed the woman, gathered around her in a corrupted halo, and gleefully fed from the dark emotions rolling off of her in waves. Her intentions were easy to read; her black heart spread bare before his eyes. She was wicked with a withered husk beating in her chest, and planned to use the child that unconditionally trusted her until his body collapsed. Depraved, twisted things awaited the boy that would surely utterly destroy him until death took him, be it by injury or his own hand. He would be lucky to die quickly, but would likely sob till his grave.

Satan continued to walk away, ignoring the unfolding tragedy. What did he care what happened to some brat that wasn't Yukio?

Except…

What if that _had_ been Yukio?

Yukio wasn't slow like the idiot child casually holding hands with his doom, but things could happen. Usually kidnappings weren't so…clean, and force could be used if someone was uncooperative. Satan hadn't cared about the abductions that had been taking place last week in the city, but seeing one happen before his very eyes reminded him of the bits and pieces he'd heard. They were both children around Yukio's age, with dark hair and unusually bright eyes. If there was a preferred target, then, if there was even a hint of a chance of future danger, then Satan would completely and utterly crush the threat.

"Hey!" Satan shouted, and he felt pleased when the woman froze in fear, "Where're you going?"

The boy smiled, still unable to understand, "Rin, hi! Have you met this nice lady?"

"No. So…Where're you going?"

"Oh…" The woman looked caught off guard that she'd been called out. It probably hadn't ever happened to her, what with her looks and friendly superficial presence that wouldn't lead anyone to doubt her. But she saw he was (physically) a child and plastered a motherly smile on with flawless precision. "I'm just buying lil' Satoru here ice cream."

The demons around her buzzed excitedly and Satan met her bright green eyes. They were warm and friendly, and anyone else would have missed the way her eyes assessed him, picked him apart. She was judging him for some desirable trait and Satan hid his own intent behind his own wide eyes. Maybe it was because he and Satoru looked similar, maybe it was because he wasn't nervous around her like any other child with common sense and decent parents would be, or maybe it was the simple chance to scoop two children up in one go. Whatever it was, she found something she liked, and, with poisoned kindness, "Would you like some?"

Satan imagined turning the woman into a red smear and smile brilliantly, "That sounds great!"

The woman, fool that she was, held hands with her doom.

* * *

Satan sighed and absently used one of the pencils from his bag to pick the flecks of blood from under his fingernails. Despite his initial thoughts, the kidnapper lady hadn't been that bad. After his gracious host had shown him to her home and her giant of a partner in crime, she'd been generous enough to let him have some of her spare children's clothes when his had gotten dirty with her blood. She'd even given him some of her prized perfume to cover up the smell of blood and her burned flesh. How thoughtful!

Satan snickered wickedly, mood light and airy from his recent stress relief. Sure, the annoying priest would probably wonder why he had new clothes and smelled like "Summer's Bliss" (humans had the strangest names for things, honestly), but nothing the fool could say would bring his mood down. The evidence was long gone, burned to ash by pretty blue flames, and it'd be easy to make an excuse for his late arrival. It'd all been worth playing a fool for a while; not only had he gotten a chance to relieve some stress but he'd also eliminated a potential threat to Yukio very, _very,_ thoroughly. He'd only needed a single look at the children in cages to know he'd made the right choice in being proactive.

When he'd finished having fun with the two victims, Satan hadn't felt the need to kill the weak kids on top of everything else. He wouldn't get nearly the same rush when his enemies couldn't at least pretend they had a chance. Some of the brats might talk, sure, but no one would believe them. They were all terribly scared children who'd be babbling nonsense about demons thanks to a quick burned Temptaint, until they either wised up and quieted or were thrown into an insane asylum.

After all, there was no way a seven year old could possibly overpower two adults three times his size, much less rip off that bear of a man's arm. The clawed open chest cavity would forever baffle them, and the lady's legs must have been bashed with a sledgehammer with how many pieces her bones were in. How and why the two bodies were charred black would probably be the main mystery detectives would discuss in vain for _weeks_.

Nails clean, Satan checked his appearance one last time before he entered the monastery. Flawless by seven-year old standards. The wards made his skin prickle for the first time in years and the demon frowned. So maybe he'd overdone it and let a little too much of his demonic power bleed into his body, so what? He didn't really care; anything to protect Yukio, but it might set off the priest. It was already going to be an ugly enough argument since the bastard didn't like it when he stayed out after dark. Satan, however, knew he could take care of himself and didn't listen to any rules except the sparse ones he set for himself. He'd come and go whenever he damn well pleased.

Oh well. He'd just say he lost track of time playing a game with some new friends.

He'd absolutely slaughtered them, so it'd been a real good time.


	8. A Storybook Ending

Chapter 8: A Storybook Ending

 **If Yukio were older, he probably would have thought more about the stories Rin told him.**

* * *

Yukio was pretty sure he was the only one who knew just how good his brother was with words. No one thought Rin could do anything but hiss and curse with a disrespectful drawl and plenty of spite. It was because of that, no one ever thought Rin could weave a story, but time and time again Yukio saw his brother lie…no, twist and change the truth until things favored him more. A different word here, a controlled reaction there, and suddenly he could wiggle his way out of most trouble without anything noticing. Yukio knew it was wrong, dad told him lying was bad, but he couldn't help but be fascinated by how a little lie could change things for the better.

So, maybe Yukio had started practicing lying a tiny bit more than he should. If he could change a situation for the better just by changing a few facts, if he could keep Rin out of trouble by lying to the teacher, then what was so wrong with that?

Besides, Rin's ability to lie was what probably made him such a great storyteller.

Rin would tell Yukio elaborate stories whenever he got the chance. Sometimes it was throughout the day when they had free time, other times it was late at night, when they really should be sleeping but were being naughty and stayed up with flashlights under the blankets. No matter the time or place, they were stories Rin would tell him and only him, never with anyone else around. Yukio wasn't sure why, since his brother's stories were amazing, elaborate and giant tales about great battels and fights, so why wouldn't he want to share them? They were a whole lot better than the short stories that didn't really make sense other kids liked to tell each other.

Most of the stories were centered around the life of a character Rin simply called "The King" and what he did and accomplished in his life. Alone in a savage and near-lawless land, The King used his immense power to bring order to that entire world and eventually become, well, the king of that world. Yukio had found it funny how bad Rin was at coming up with good names even though he was so great at coming up with good stories. But he didn't say anything after Rin gave him an annoyed look, because then the story might have stopped.

The story came in fragments, told in nearly self-contained episodes, even if there was an overarching plot that came into play. It was hard for Yukio to keep track of it all because a lot of times things that happened a long time again were suddenly important. Sometimes The King was betrayed and parts of his own army turned on him, sometimes a minor character that had only been vaguely mentioned came back as a powerful force that changed everything and very nearly destroyed The King's plans. Sometimes someone important to The King would vanished and only be found, dead, weeks later.

Yukio learned pretty early on that Rin's stories usually weren't very happy. The fighting never seemed to end, instead going on and on for what seemed like forever, countless battels bleeding into one another until it was all just one huge mess. Yukio would never know how The King kept fighting for so long when it all just seemed pointless, like nothing he did mattered. Unless Rin skipped ahead in time, every piece of the story was about killing and slaughter, with such detail it made the young boy cringe. And yet, Yukio couldn't stop listening. Rin told the stories so well and with such passion that it sucked him in and he listened regardless of his own doubts, enraptured with the tales of all The King's triumphs and failures night after night, gasping at the twists and turns, and in awe of the powerful magic and brute strength described for him. Until finally, impossibly, The King actually reached his goal and ruled his entire world. Yukio thought the story would end there, because that had to be the end right?

Except no, there was one more story Rin had.

He wouldn't admit it, because it felt really girly and he was sure Rin would make fun of him for it, but he liked that final story the most. It was so out of place among the tales of epic battles and fighting, but for some reason Yukio couldn't help but feel drawn to it. Rin always told that story differently from the rest, his voice sounding really strange and his face downcast with a weak smile. Like he was happy and sad at the same time, and there was something scary raw there Yukio couldn't help but stare at.

He never thought his brother would be one to get emotional over a love story of all things.

The story of how The King fell in love wasn't a long one, but it still really confused Yukio. The King met a girl, tried to trick her, was tricked in turn, and somehow that led to love? It didn't make any sense and Rin was unusually vague about the whole thing, only giving bits and pieces as to what had actually happened. When Yukio asked how a girl could trick someone as great and smart as The King, Rin had looked weirdly embarrassed and refused to give a straight answer. He'd tried to get an answer out of his brother, complaining that not knowing made the story bad, but Rin had just gotten so annoyed he'd turned red in the face and sputtered angrily.

Yukio decided his brother just hadn't come up with a reason yet. Honestly, such a good story and he doesn't think about how to make the ending make sense? What was wrong with just saying they fell in love anyway? That's how it always went, at least.

Even though that was the last part of the story, Yukio still had a nagging feeling that he wasn't hearing the actual end. The King and the girl didn't even get married in it: Rin just said she was pregnant with twins and ended the story without another word. No amount of pestering could get him to continue, not even Yukio's usually full-proof pouting!

"I'll tell you when you're older." Rin had said.

Why did that matter? Rin told him all about people fighting and dying, but he couldn't hear about The King and the girl he loved just a little more?

It just wasn't fair! He wanted to see their happy ending already!


	9. Claws

Chapter 9: Claws

 **Satan thinks children and sharp objects don't go together, mostly because he wants said sharp object for himself.**

* * *

Very early on, Satan had realized just how weak and fragile humans were, even after they'd grown up. They almost never developed any magic or other abilities, didn't heal very fast, and didn't have any real way to defend themselves. Oh sure, they had developed ways to fight that worked around their weaknesses, but that still didn't quite make up for his sudden lack of claws and fangs. He'd always been a very hands-on guy, so he found himself sometimes staring forlornly at his weak human nails, suddenly aware of what he'd lost. He'd gotten into the habit of filing them into points, but it still wasn't the same. The claws had been deadly and dark things he'd used to rip and rend when he'd first started learning all the intricate ways his pretty blue fire worked.

Yes, in some time long forgotten, Satan hadn't really known jack shit about his own signature power. Things were weird back then, what could he say? But he'd learned with _extensive_ practice just how precise he could be if he wanted, and enjoyed controlling the fire almost as much as he loved simply letting lose. The flames demanded that they burn and consume, so he didn't fight it and let them, but under his terms alone. An entire room could be alight with licking fire, awash with blue, and yet a single flower in the heart of the inferno could remain untouched if he so wished. It made his many (many, _many_ ) failed possession attempts all the more infuriating. He knew what he was doing, he had the control, so why then?!

It had to be because humans were fundamentally weak.

And because they were weak, without fire or claws or fangs to defend themselves with, they made fakes and thought themselves to suddenly be beasts. Fake beasts that had deluded themselves into thinking they could fight a natural-born predator who waded through their blood while they squirmed at the sight of gore and flinched from pain.

Absently, he flipped a small switchblade in his hand, testing the weight and edge against his fingertip until blood welled free. He found he rather liked it, even if wasn't nearly as sharp as his claws and snickered at the horrified look some jackass middle schooler gave him when he pointed the blade back towards him. Honestly, you'd think someone who'd been so gung-ho about getting "payback for my little brother" wouldn't practically shit himself the moment he lost his weapon. Satan was still in the body of a six year old, how imposing could he possibly be?

Very, the demon thought absently, as he made a show licking the blood dripping from his finger and saw the middle school brat shudder. He had a bad habit of playing with his food, but, well, it was fun.

The kid had nearly a foot on him, but Satan still only raised one brow when the boy recovered from his shock and attempted to loom over the demon. Attempted, because the boy refused to get within even a yard of the outstretched blade, which completely ruined even the faintest chance of the little, unimaginative, intimidation tactic of working.

"H-hey! That's mine!"

Satan stared at the boy, unblinking, for several long seconds.

The world narrowed, blurred, and then he had pinned the older boy to the floor, knife to his neck. He'd cradled the boy's head from the cracked concrete so something stupid didn't happen, and, deceptively gently, let go of the blond locks he'd fisted to keep the head steady. Absently, he let one of his sharp(ish) nails traces patterns on the back of the tensed neck.

"You really don't know anything, do you, vermin?"

The idiot who'd attacked him really wasn't suited for fighting. He'd frozen, suffocated so thoroughly by his own fear he didn't even realize he could have tried to call for help. Well, at least the fuck moron hadn't pissed himself. Yet.

"You see, you fucking lost. And the loser has to give up something."

Satan let his nail, as dull as it was, ghost up the side of the boy's neck, absently resting on his pulse point before moving on, dragging up inch by inch with each word, "It can be anything really. I'd say your pride would be enough, except you clearly have none. So I decided I'd take your pretty little knife." His hand had reached the boy's face, tiny and hardly able to eclipse it like he would have liked. But it was enough, and he slowly traced a trail up to the boy's watering eyes. He let one finger lightly press down when the next blink came. Not enough to hurt, but to keep the lid closed.

"But it _is_ a rather nice knife, so I can see why you'd want to keep it. I still need something of yours, however. Now, if I don't get to keep the knife then what…."

He slowly increased the pressure until the boy gasped in what he probably thought was pain. No, this vermin didn't know what _pain_ was, and in another time, another place…

"…should I get?"

Satan got a very generous gift that day. Which was to be expected; he taught that boy a very valuable lesson and it only cost him a weapon he couldn't even use properly anyway. Well, that and any sense of pride he had.

His eyes were an ugly brown anyway.

"They'll never believe you. And you'd have to admit you tried to stab a grade-schooler." Satan said when he'd released the boy.

"You…You're not human! You're a demon!"

Satan laughed till he was in stitches, and returned to the monastery in high spirits.

* * *

 **Prompts considered.**


	10. Thrall

Chapter 10: Thrall

 **No matter what anyone says about him, Satan knows he's not nearly as shallow and petty as people think. When he wants to be.**

* * *

Satan was dancing.

It wasn't anything fancy, more the simply the sway of his body to a tune that sounded watery and far away. No, the music that drifted in and out of focus wasn't nearly as important as the delicate body held in his arms. Tiny and breakable, but also filled with a deceiving power and fiery will that was so strong and bright his heart ached with even a glance. She's scorched his hands before, looked him in the eye as her equal, and, somehow, they'd reached the understanding he'd always fantasized he'd one day find. Too perfect, too amazing to be his, and yet she held him back, rocking with him to the slow hum of the tune. And this time, it was _real_.

As if sensing his thoughts, Yuri smiled sweetly and squeezed their entwined hands just a bit tighter. She didn't shy from the hidden claws that still lightly poked her hands, didn't flinch from his pretty blue flames that likes to reach out and tickle her, and didn't so much as bat an eye as his other very inhuman features. She stole his breath, embraced him, and was more than he'd have ever let himself expect.

They made quite an odd pair, honestly. Anyone else would have thought Yuri was simply pretty at best, but too homely to really give a second look. To be perfectly honest, Yuri couldn't hold a candle to the lines of absolutely flawless demonesses that would throw themselves at him, with plump chests and shapely hips and a perfect face. So very few would ever truly understand why he'd picked Yuri of all the women in the worlds, never even considering his heart. That he'd had a heart he'd buried until the woman just as fiery as his flames dug it up and, somehow, found beautiful.

He loved her, so it was stupid, really, that'd he'd never gotten around to it until now. It was a tiny little thing he'd never done that kept nagging at the back of his mind. Three little words, as cliché as it got, and yet he'd never said them.

Yuri didn't mind, instead tittering cutely whenever she said those words to him and he only mumbled something incoherent back. She knew how he felt, probably before he'd even admitted it to himself, and it was enough for her that he was honest through actions instead of words. But he didn't want him to be 'enough' for her; no he wanted, more than anything, to be her 'everything'.

Well, ok, maybe not her 'everything'. That wasn't exactly possible when he could see his two (adorable) brats peaking in from one of the doors to the side. Even less so when Yuri was taking the initiative and had decided she'd round up his estranged children to have "family bonding time" with. Normally he'd laugh himself sick at the dumbass who tried to order his kids to do anything, some of them had tempers that put his to shame, but Yuri was a completely different case. Considering how she'd single-handedly thwarted his original plans to possess her with nothing but shitty stick shift and environmental (in)convenience, he was sure at least half of the menaces would be here within the week.

Because a law of the world was that somehow, someway, Yuri would always manage to have her way. And because she was ridiculously sentimental and determined to somehow be even more perfect, she'd learn every one of his weakness and faults and fulfill even the faintest of wishes he refused to voice. She was amazing and perfect, and Satan knew she deserved to hear his love for her. It was only fair he finally granted one of her unvoiced desires.

"Yuri…I-"

Without a word, Yuri dissolved, turning to ashes in his hands. Like always, she'd never hear it, because he'd was-

Satan awoke and knew, without any doubt, what day it was.

He sat up slowly, taking time to rearrange the tiny arms around his waist. Honestly, the separate beds did nothing to stop Yukio from crawling under his covers every night, and Satan was in no rush to stop it. He was precious and tiny and it made it all the easier to protect him if something ever went wrong. Shiro was too soft and far too invested to ever suddenly change his mind, but he knew damn well he'd done little to endear himself to the other exorcists. He was pretty sure they all respected the shitty priest too much to ever try anything (for some reason) so he was fairly confident nothing would change when it'd be eight years now. But he couldn't ever be too careful.

The faintest trace of pink licking the sky told Satan how early it was, and he sighed. He always had the same dream on this day every year. It wasn't unpleasant, but it felt like his own soul was mocking him.

' _See, see what you'll never have? You should have tried harder. But because you were afraid, you lost everything.'_

Not everything, Satan remained himself. He spared a moment to admire Yukio, his first real child. He'd had many children, but they'd never truly been _his_ children. A contradiction, since Yukio had so little demon in him he'd be human for the rest of his life unless something drastic happened. It had nothing to do with his apparently uninheritable fire, and everything to do with a level of nuance he was sure few expected him to be capable of.

Grinning, Satan lightly shook Yukio awake. The boy was groggy and stared blankly ahead as Satan slipped the glasses on. The sudden sharpening of the world seemed to do the trick and Yukio yawned, rubbing his eyes under the glasses. Then, with a grumble, Yukio buried his face back into Satan's chest and did his best to fall back asleep.

Now it was time for the magic words that would surely do the trick.

"Yukio, it's your birthday today."

Shiro's pained yelp as sixty pounds of excited child woke him up via flying tackle always brightened Satan's day. Yukio was shouting excitedly for him now, probably to get his help in physically dragging Shiro out of bed and ready so they could open presents a whole two minutes sooner. Obediently, Satan trotted into the room, laughing at the resigned look at the shitty priest's face as he did his best to deal with an excited and newly-minted eight year old. So Satan _might_ have done his best to work up Yukio last night about his birthday and the presents.

It was all about being there, in the end.


	11. Birds of Feather and Flame

Chapter 11: Birds of a Feather and Flame

 **Satan will never find fire to not be useful. Even if it isn't his.**

* * *

"Look, Yukio, watch."

Match struck, Satan lite the paper on fire. For a few seconds he held it and watched the flames blacken the paper, eating away the white with licks of red. It wasn't blue like he'd have preferred, but it'd do its job and, in a few seconds, the paper was ash on the wind.

"And like that it's gone. All of the bad things they said, all of their efforts to get to you are gone in a couple of seconds. See, they aren't that big of a deal. Now you do it!"

"Ah, but fire is..." Bad, scary, painful, was everything Yukio had been taught.

"It won't hurt you if you don't let it. Look." Satan took Yukio's hand and, together, they made the motion of striking the match. Yukio flinched at the tiny hissing sound as the flame sputtered to life, spitting like a snake. But the demon holding his hand refused to let the boy let go of the flickering flame. "Look. You're the one who brought it into existence. And, if it ever gets out of control or disobeys you…"

Two fingers suddenly pinched the fire from existence.

"Gone. Sadly, people aren't so easy to deal with," Not unless an opportunity came up, at least, "…But it's the same principle. If someone gets in your way, you just have to be bigger and stronger and they won't stand a chance."

Yukio felt unsure- shaken actually. His big brother always seemed to know exactly what he was talking about, always knew all those big words adults liked to use, and was so sure and confident about everything, so unlike himself. Yet the words caused something uneasy curl in his gut, restless, and made the boy shift from the heavy feeling. He felt like there was someone that wasn't being said, something…weird. The air felt tight in his throat, and he wanted to throw his brother off his back, free himself from the sheer _presence_ Rin suddenly seemed to have. But he was weak, he couldn't find the strength.

"Rin…"

The weight was gone and tension evaporated when another match was waved between his eyes, bumping Yukio's glasses lightly. He flinched back in surprise and looked up to see an impatient Rin, who kicked a stack of papers and old notebooks, "Come on, this time you have to do it yourself. I want to see those shitty notes burn already!"

"Rin, you shouldn't swear! Dad will get mad!" And then there'd be fighting and yelling and…And maybe Yukio was weird, because he didn't care when Rin shouting himself hoarse at the other kids, but it _bothered_ him when his twin and father fought. With anyone else, it didn't matter, but…

"Too fucking bad! I don't care what that shitty old man thinks! I'll say whatever I damn well please!" Satan proudly declared, sprinkling in extra swears for effect. Honestly he was doing the shitty priest a favor! If he was so bothered by a few generic words, then he needed a thicker skin! But not too thick; it was great stress relief to tear the Paladin down.

Yukio fidgeted, words coming out almost silent, "But…but I don't really like it when…"

"When…?"

"Never mind…"

Satan mentally filed away the strange reaction to pull apart and figure out later. "Oh ok. Well come on!"

Yukio fumbled enough matches that eventually Satan sighed and took the box. With practiced ease, he lite the match and handed it to Yukio. The boy panicked for a moment at suddenly holding dangerous fire between his fingertips, but calmed down quickly. Unnaturally quick, in fact, and the demon lightly cuffed Yukio over the head when he realized the young boy was staring a bit too intensely at the match. He dropped the match, but Satan didn't really care.

"Don't do that. If you overthink it, you'll just get burned." And blue haze was a _bitch_ to recover from, both mentally and rebuilding everything that'd been burned down.

The second strike Satan made was practically synced with the back door opening. The moment froze, suspended as Shiro, unknowingly, stared down the ruler of Gehenna with nothing more than a sigh and a quick prayer for strength.

"Rin. Please tell me you aren't about to-"

Expressionless, Satan dropped the fire and the papers at his feet turned into a ball of flames. Shiro didn't even react except to remove his glasses for a second and attempt to ward off a headache. "I can't believe you're a pyromaniac…" Except the Paladin very well could, and it frightened him that it'd simply become an aspect of one of his children.

"I'm not a pyromaniac."

"Of course you aren't" Shiro deadpanned and turned back inside to find one of the many fire extinguishers he'd started nearly obsessively hoarding.

He really, really, _really_ , should have taken Rin to a psychologist a long time ago. Except he wasn't quite sure he wanted someone to take an in-depth look into Rin's psyche, not when he wasn't sure how well things like therapy and, lord almighty forbid, drugs, would interact with his not-quite-human mind and body.

Against his better judgement, he'd voiced a few of his concerns for Mephisto only to be laughed at and have his worries waved away. Because almost all of Rin's violent, possessive, and outright defiant behavior was completely normal for a "healthy, growing, demon looking to prove himself and claim territory".

Shiro very nearly strangled the man.

There was no magical answer to his problems, nothing that would solve the gap between himself and Rin. Mephisto was useless, blaming _Shiro_ for doing something wrong because, by all rights, he should have been claimed as Rin's 'territory' just as Yukio had been. It was apparently all very unusual, Rin, as young as he was, seeing Shiro more as competition for Yukio's affection that a father figure, or, at the very least, a caretaker. So since it was all surely Shiro's fault, he'd better figure out how to fix it and make nice with Rin.

Mephisto had enough tact to not outright say it, but the Paladin knew what he'd hinted at.

It was a disaster in the making.


	12. Building (1)

Chapter 12: Building

 **It all had to reach a breaking point sooner or later. In Satan's life, it's always sooner. Always.**

* * *

Yukio looked up and then away, feeling embarrassed and worried. Beside him, his twin, Rin, just looked annoyed, hands on hips and glaring at the gutter where the ball had been caught as if it'd suddenly move under from sheer willpower. Yukio wouldn't have been surprised if it did. His brother's glares were just that scary, and Yukio knew he wasn't the only one who thought that. The teachers always clammed up whenever Rin glared at them, and they were adults! Only their father had grown immune, and that was just because of how often he and Rin fought…

Yukio decided to swallow the bitter medicine and take the blame. It was all his fault for throwing the ball too hard. Even if Rin had been trying to teach him, it was still his fault. Besides, he'd rather dad didn't get involved… "Um…I can go get dad, and maybe he…"

Satan felt his hackles rise at the mention of _that man_. Now that he'd adjusted to his body, Yukio didn't need to rely on that Paladin for anything but free food; Satan would do everything else for him! "No! I'll get it myself!"

"B-but Rin! It's so high up!" And stuck right in the middle of the gutter, away from the sides and places where it might be easier to reach. Yukio knew Rin was strong, but if he fell from that high up…?

"That's why I'll climb."

"But what if you fall?"

"Then I just won't fall. Simple."

"Rin…"

"Have some faith in me, would ya? I'll get the damn ball back and that shitty priest won't ever even know. Then we'll get back to business. I think you might have a future as a baseball player- you have a good arm on you." Satan noted, and smiled as Yukio flushed at the praise. His son's aim was uncanny even with glasses, and he swelled with pride at the unnatural accuracy.

Though the demon blood running through Yukio's veins could be measured in drops, now and again Satan saw the signs of it. Bursts of strength were a bit rarer, but he'd noticed that there was quite a nasty temper hiding under that meek exterior that was absolutely _vicious._ And maybe it was just Yuri's perfect genes, but Yukio was incredibly smart, outperforming his peers by leaps and bounds with discipline beyond his years. Satan would cultivate these traits, slowly but firmly force the boy's shell open, and raise him into an unshakable and strong pillar who none would dare cross.

But for now he had to keep the shitty priest out of the way. There was no way the fool would have approved of Satan's method of teaching, even for something as simple as throwing a ball properly. "Pretend your target is the face of that retarded idiot from school" was highly effective at drawing out Yukio's inner strength once he poked it a bit (it was cute that Yukio got noticeable worked up if Satan added "was being mean to me") and Yukio absorbed the form corrections like dry wood did fire.

But no, the Paladin was doing his best to try and teach the both of his 'sons' how to solve issues nonviolently. And while even Satan could agree violence wasn't _always_ the answer, there were very few situations where a show of force wouldn't be useful. Mouth-breathing idiots who picked on Yukio? Teach Yukio ways to show off just how strong he could be and scare them away. Once Yukio's accuracy in general increased, Satan would see if they couldn't move up to knives. Deadly, sharp, easier to get than a gun in this stupid country, and with the added bonus of striking primal fear into hearts the way only claws could.

And if seeing that didn't scare the crap out of those brats, then Satan would just beat them up. Again.

Satan hummed in thought as he easily climbed the vertical pillar supporting the patio overhang. It'd be a bit tricky to teach the intricacies of the motions of knife throwing, but it'd be well worth it. A quick dip into some Holy Water he'd stolen from the shitty priest and Yukio would have his first way to defend himself from demons. Fighting lessons were a must now that the childish wobble had started to leave Yukio's limbs, though Satan wasn't expecting much when his son was so obviously a ranged fighter. And even that much would be hard with how much of an affect the shitty priest was having on Yukio, but Satan was sure he could undo all those idiotic teachings fairly easy. If nothing else, the man couldn't say that it was a bad idea for Yukio to learn how to defend himself, and it'd be easy to slip offensive lessons in. Not that Satan was going to share something that important with anyone in the first place. Oh no, _he_ was going to be the only on to teach his child the really important life skills! And there was little more important in Gehenna that learning how to beat the absolute shit out of someone.

He didn't consider himself sentimental, but the thought of Yukio one day breaking some fool's kneecaps threatened to bring tears to his eyes.

The gutter creaked ominously under Satan's weight when he grabbed it, dragging him back to reality. He cursed the contradictory thing: what was its use when it was too weak to support him, but too strong to not drop the ball? He'd have pulled the entire thing down with his growing strength then and there, but it would just mean dealing with those worried glances from the shitty priest as the idiot worried his 'heritage' was peeking through. The moron thought he knew _so_ much, when really he didn't understand a thing!

"Rin!"

"I'm fine!" Satan grumbled, and thought for a second, still clinging to the support beam like a particularly aggressive koala. He drew himself tight and tensed his muscles, pulling all his power inward before letting it explode outward with a heave upward. Satan leapt straight up, missing the gutter by an inch, and lashed his hand out towards the slopping roof, fingers catching the edge of a tile. With a grunt, the demon hauled himself onto the roof, skipping the rickety gutter entirely except when his foot kicked it.

Yukio gasped at the feat, expression filled with nothing but childish awe and near-worship that sent bubbling, giddy, feelings flowing through Satan's chest. He grinned and flashed an exaggerated thumbs-up at Yukio, who's eyes somehow grew wider. "See, I told you everything would be fine. Looks like you were wrong."

Yukio flushed, embarrassed, "R-right…"

"Huh, what was that? I didn't hear 'you're the bestest, most reliable big brother ever!' you know!"

"Bestest isn't a word…"

"Huh, you're right. Good thing you're so smart." Satan faked surprise and grinned at Yukio's stuttering. Perfect. "Here, catch!"

Yukio fumbled the ball, nearly losing his glasses, but it didn't matter to Satan. Now that his hands were free, he could see about getting down-

"Rin, what are you _doing_?!"

The shriek, nearly hysteric with fear, startled Satan and his head snapped toward the offending sound to see one of the clergymen. A roof tile slipped free and Satan fell forward and off the roof, bouncing off the rusty gutter and suddenly airborne. The idiot had frozen up, and Satan had just enough time to spot the stupid look of surprise before the world tilted too much. He caught a flash of greyed hair, and there was the shitty priest, screaming, tearing his way across the yard, but he was too far away to even have a chance. Satan hit the ground hard and at a terrible angle, his back and shoulders taking the brunt of the force and his head snapped to the side. If he were anyone else his neck would have snapped immediately, but Satan just hissed at the sharp pain and fell limply on the ground to wait out the dizziness. He might have blacked out a little bit, because suddenly the shitty priest was leaning over him, lightly slapping his face and yelling about staying awake.

That didn't matter nearly as much as a sobbing Yukio, and he tried to push the shitty priest away and reach his child. It was wrong for Yukio to cry over him; he was the strong one who did all the worrying and tears were wasted on him. Except he felt weak, a bit dizzy, and he realized he was bleeding a whole lot from where he'd cut his arm somehow. He groaned as he was carried inside, hating every second and doing his best to will away the spinning. He was flipped and prodded uncomfortably, but didn't resist, recognizing a check for wounds instantly. The treatment was quick and effective, calloused fingers steady as they cleaned his injuries and tied them tight.

At some point when he was trying to not pass out, Yukio must have spilled the entire story, because when Satan finally sat up, feeling considerably better, Shiro was there, looking stern. An actual child would have coward, but Satan just met the look with an unamused glare.

"What."

It wasn't actually a question, but Shiro took the invitation anyway, "All that for a ball? You should have just called me, I would have-!"

Oh no, this was in no way _his_ fault, "If the fucking idiots _you_ employed didn't have the worst timing everything would have been fine! I almost had it!"

"You shouldn't have been so reckless!"

"I can do whatever I damn well please, you shitty priest!"

"How many times do I have to tell you to not-? Why are you always _like_ this?"

"Because fuck you! You aren't my father!"

"Why won't you let me at least try? Rin, you could have _died_ , I thought you broke your neck!"

"It's still all your fault! Teach those fucks some common sense!"

"I-"

"It's all my fault!"

The screech stopped them both short, and Satan realized he'd forgotten Yukio was even there. Yukio, who was crying a fresh wave of tears, but doing his best to look determined, "It's all my fault! I…I wanted the ball, I told Rin to go get it, I'm sorry, I'm sorry! It's all my fault so please just stop it! Stop fighting all the time over me…"

"Yukio…" Satan reached out, but Yukio shook his head furiously and refused to look up.

"Please stop…"

Shiro seemed to reach some sort of internal conclusion, because Satan could see him gather up his pathetic resolve and steel himself, "Yukio, you're right. Please, go upstairs. Rin and I need to talk."

"I'm not saying _shit_ to you-"

"Then you can at least listen to what I have to say." Shiro's voice was short, snapping and with no room for argument. Satan hadn't thought the man was even capable of actually asserting himself, and was shocked into silence. That was all, he told himself, as the Paladin (and for the first time, that actually meant something) continued, gently, to the youngest there, "Yukio, Rin and I really need privacy. Understand?"

"Yes…"

The young boy nodded, wiping away his tears on his sleeve and turning to leave. He hesitated at the door's threshold, looking as if he'd fall apart as he looked back with tear-stained cheeks, "Rin…Please just…"

Yukio's words failed, and he fled with a whispered "Sorry…".

The door clicked shut, suffocating the room with silent tension. Rin was a drawn bow; ready to fire biting retorts the moment Shiro so much as opened his mouth. The Paladin took a long moment to wonder just how his greatest adversary had become the child he'd adopted, and not some great demon. It made a sickening amount of sense- Rin was Satan's child through and through, and with the greatest demon rumored to be absent, wouldn't it just be perfectly ironic for Rin to take up-

Shiro crushed the thoughts underfoot before they could plant doubt in his heart. No, he wouldn't let what ifs taint his thoughts, "I know you don't like this, Rin, and I know you're only doing this because Yukio asked, so I'll keep this quick, ok? I just want to know one thing, Rin. One thing, and I'll leave you alone, ok?"

"Fine." Anything that would make this farce end quicker so he could see Yukio without any annoying interruptions or-

"Why are you determined to hate me?"


	13. Catharsis (2)

Chapter 13: Catharsis

 **Continuation of 'Building'. I swear to god this story was originally meant to be nothing but cracky fluff.**

* * *

" _Why are you determined to hate me?"_

It was a ridiculously question. Why hate the shitty priest? Why shouldn't he hate the filth that pervaded his life? He almost laughed bitterly, but instead Satan found himself up and storming away without a word. Or would have, if Shiro hadn't grabbed his wrist with surprising strength and iron will.

"Let go of me." Before he did something rash and finally acted on his urge to rip the man's throat out with his teeth.

"No. We are going to settle this here and now." Shiro pressed forward, damn the consequences of now because what _would_ inevitably happen later otherwise was so much worse, "Can't you see what this is doing to Yukio?"

The demon snarled, ripping himself free from the shitty priest's strong grip and whirling around. He was practically crouching, wound tight and ready to lunge. It had to happen someday, and today seemed like a great day to finally claw the cancer out of his life, "What the hell do you care about Yukio? He isn't your kid!"

A part of Shiro almost wished he'd done what so many other foster parents had and hadn't ever mentioned how adoption worked. Except no, he wouldn't have been allowed to: Rin was too smart and too confrontational for that to not have ended terribly, "Maybe not biologically, but he is still _my child_ , and I won't let anyone hurt him. Not even you, Rin."

Satan hissed, insulted beyond words, "I would never-!"

"Maybe not today, maybe not tomorrow, maybe not even years from now, and maybe not ever. But today you could have died. Rin, I almost had to explain to Yukio that his big brother was _dead!_ " Shiro realized he was shouting now and breathed deeply, drawing his calm inward and expelling the anger, the fear, "I won't let you do that to him, and I won't let you continue to hurt him."

"I do not hurt Yukio."

It was a statement of fact, and Shiro realized just how hard this was going to be. How was he supposed to convince Rin to see beyond himself for once? "Yes you do. Every time we fight, we both hurt him a little bit more. Every time we fight, he isn't sure whose side to take: his loving father or his precious big brother. Picking a side means losing someone he loves."

Satan sneered. Like that mattered to him. "I wouldn't mind if he lost you-"

"But Yukio cares! Whether or not you like me isn't the point, you two are different! Even if you hate me, Yukio doesn't, and you can't change that!"

"I'm not-!" Not ignoring Yukio's feelings, except the words, as soon as the swelled up, tasted familiar. Something Satan knew intimately, bathed in and spewed so regularly there was no way even the slightest hint of flavor would escape his tongue.

A lie.

"I'm not…"

Except he was. All because he was so _old_ and knew things Yukio couldn't about the Paladin before him. Hidden under all that fatherly kindness was a man who'd taken everything from him without a thought, without caring that it meant he had to destroy someone else to steal from the devil.

The sudden silence was hungry, devouring the raging emotions trapped in the room. Shiro saw Rin visibly slump, the will to fight slipping from the boy's heart like sand. Except it was a lie, an illusion brought on whenever one was forced to come to a realization they hated. There was only of two ways this would go, and Shiro already knew Rin well enough to see it building.

"If this goes on, it won't be just me he hates, Rin. He'll hate both of us, and he'll hate himself."

The emotions burst, scattering ugly bits and pieces of "What the fuck do you want? For me to love you, for us to be a _happy family?_ Like hell!"

Shiro had damned and burned others once for his faith, why wouldn't he do it again? This was all fake, some lie the _shitty priest_ indulged himself in to rid himself of his guilt. Satan was happy to play along for so long as it benefited him, but he wouldn't _ever_ let his guard down. The man had no real will of his own Satan had decided, but was a strong puppet. A strong puppet that might be fine playing house for now, but one day he'd have to _burn it before it took away his heart again._

"Rin, I'm not-"

"Shut up! Do you think I'm fucking stupid? Adopting Yukio and I, trying to pretend that you care? This is just some game for you isn't-"

The sound, almost like a whip crack, echoed in the small room. The pain registered only faintly, an afterthought even as Satan gingerly touched his redden cheek. Slowly, he turned his head back towards Shiro, seeing the man standing tall, hand still raised and fury in his eyes. Cold, calculated, detached, eyes that looked down on him with disappointment.

Shiro's voice was thunderously even, sharp words spoken with absolute authority. "Don't you ever even imply I don't care for you and Yukio, Rin."

But Satan didn't hear a word of it, his ears ringing and the room spinning with the sudden rush of raw feeling. He'd always had a bad habit of letting things fester in his heart until it rotted away to nothing. Yuri had noticed, scolded him for it, and insisted he open up to her gentle eyes. She'd been the only one who'd known what the devil kept locked up in his heart, petty little worries and insecurities, and she'd taken it all in stride.

Yuri.

Yuri, who was no longer here.

Yuri, who was no longer here, because of the Exorcist before him.

The giggle that bubbled up from the depths of his blighted chest was the sound of a falling blade.

"Ha! Resorting to violence already, are we? Finally!"

And then Satan had tackled Shiro, hands wrapping tightly around a neck between one blink and the next. The weak skin gave under his grip, choking the shell-shocked priest in a matter of seconds, and toppling him to the ground. Satan kept his hold the whole time, feeling a mad grin pull itself onto his face. Ah, he must really look like a demon now, the smile tearing his face in half and eyes dilated as he let the bloodlust peak.

"I don't care what you say, you _fucking priest_ , but I won't let you trick me! I know your game; I know you'll get sick of us both one day, and then what? I know what you'll…do…?"

Arms had encircled him, pulling Satan _closer_ instead of pushing like a filthy Exorcist should have. Embracing his violence, embracing his madness and raw feelings even though he _should run, should be afraid, he should hurt me._

Slowly, Shiro spoke through a grip Satan hadn't even realized he'd slackened. Choked, wheezed words that should have meant nothing to a demon as ancient as him…and yet those very words broke something inside him. Something that screamed as it died, clawing and scrapping at his very heart as it shattered to pieces. It took something with it, leaving his heart scrapped raw of…something.

Satan stood, feeling…odd.

Different. Almost as if he could finally- No. No, there was no way.

When Shiro stood with a handful of coughs and only an absent rub at the nasty handprints collaring his neck, Satan let him. The demon looked up at the man, face carefully neutral.

"You're serious?" He asked, even though the pure truth of the words rang in his ears.

"Of course," Shiro winced at the sound of his own wheezing voice. Rin had…quite the grip, and he potently ignored how close he'd come to being strangled to death, "what do you take me for?"

An Exorcist, Satan thought bitterly, but it was distant and fleeting, "If you're lying, I'll fucking kill you."

"I'd expect no less," And maybe that statement was a little too accurate Shiro thought, swallowing a few times in a vain attempt to sooth his abused throat, "But I do want you to stop pretending that Yukio wants the same things you do. Because right now, he just wants us to stop fighting."

Satan arched a brow. The demon would have thought the traumatic experience of nearly being choked would have shifted the shitty priest's priorities a little bit, but apparently not. The man was nothing if not persistent and laser-focused when he wanted to be.

"Can you do that, Rin? You don't have to love me, or even like me, but can you stop taking every chance you can find to try and hurt me?" Maybe Shiro was being too generous when things had finally escalated to physical violence, but there was…something in Rin he couldn't just ignore. No, the boy couldn't possibly be a true demon if such simple words could calm him.

The king of Gehenna huffed and turned away, "No promises."

"Thank you, Rin."

There was no acknowledgement that Satan had even heard as he threw open the door and walked out. He felt entirely too tired and wanted nothing more than to sleep even when it was barely past noon, and the door slammed behind him.

Shiro chuckled- he'd seen the half-misstep Rin had made.

And then he winced. Right, first his throat.

* * *

"Are things good between you and dad now?" Were the first words Satan heard when reached his room. Yukio has set aside his homework and looked up at his twin with bright, clear eyes.

Something about that nagged Satan, but he was still too confused about what he'd just done to really think about it. Were things between he and Shiro good now? No, certainly not, not even after…that, but maybe he could finally let go of some of his paranoias. Not today, and not all of them, but surely, there was more to that man than-

Satan cut the thought short. That was dangerous territory to get into, "Well, I wouldn't say good, but…Alright. Sure, let's go with that."

"I'm glad."

There was something wrong with the way Yukio said that. He looked just a little too smug, almost like he was pleased with himself. But what could he…?

It clicked and Satan whirled, gaping as he tried to find the words, "You…! You little-!"

"Me?" Yukio might have tried to sound oblivious, but he suddenly looked just a little panicked, and Satan knew he had him.

"Don't act all innocent! I see right through you, you faked all that!"

There was a moment of flailing, but Yukio knew he'd been caught, "Well, not all of it. I really don't like it when you and dad fight…I'm sorry, Rin!"

That…He wasn't sorry at all! Yukio was Yuri's perfect child, smart, kind, everything good in the world, and yet…! And yet-!

"You lied to me! Lied! To me!" Satan gestured frantically, trying to make sense of his world again. It wasn't even that Yukio had lied, as impossible as that seemed, it was..."And it _worked_!"

Yukio might have been worried, except Rin had a stupid, disbelieving, grin on his face. Lies were bad so you weren't supposed to tell them, and their dad was always disappointed when someone lied, so why…? "You're not mad?"

"Mad?" Satan squawked and pounced, Yukio squeaking as he was swept up in a suffocating hug and off his feet by uncanny strength, "No, I'm so proud of you! I'm finally rubbing off on you!"

It was incredibly reassuring to have proof that Yukio was _also_ _his_ , and a knot he didn't even realize existed loosened, uncoiling tension in his chest.

He set Yukio down and patted him on the head with an unnerving smile, "Oh, but don't ever lie to me again, ok?"

"But you-"

"It's my fault for being tricked," A dangerous policy, but only for the fools of the world, "but now that I know you can actually _lie_ , well, you won't ever fool me again. You're free to try, but if I catch you lying to me, well…" Satan leered, and gestured with his hands.

Yukio visibly paled and nodded furiously. He scampered away with the sound of his brother's unnerving cackling echoing in his ears. A teasing drawl of his name made the young boy shudder in fear.

Why oh why did he have to be ticklish?

* * *

The next day, when the other Exorcists questioned the bruised they could see peaking above Shiro's collar even after he'd pulled it high, he wove a very elaborate, _very_ detailed story about a late-night rendezvous with a, ah, very 'blessed' woman until he was waved off. His men clearly didn't believe a single word of it, but they at least trust him to tell them if something serious had happened.

If only they knew.

When Rin snorted juice up his nose at the not-so-subtle innuendos Shiro had made (much to Yukio's confusion), the Paladin easily put the thoughts of yesterday behind him for more pressing matters. The greatest being checking the parental controls every electronic in the house. Rin's smirk had been _far_ too knowing for any eight year old.


	14. Snapshot

Chapter 14: Snapshot

 **When Satan finds something he likes, it's his. Now if only everyone else would realize that fundamental rule of the universe.**

* * *

 _Click!_

Shiro stopped mid-word, blinking spots away from his eyes. He wasn't irritated, no, if anything he was vaguely amused by the entire ordeal. But only vaguely because, as usual, Rin was being stubborn.

"Rin, if you would stop and give me back my-"

 _Click!_

This time he gave into the urge to wipe away the discolored shapes dancing in his eyes. He could hear Rin snickering at his predicament and clearly enjoying his discomfort. Well, he couldn't expect things to change overnight.

"Mine now." Satan hummed, admiring the camera the shitty priest had let him hold to 'look at'.

Except it was clearly expensive and had a lot of interesting settings, let him take less than flattering pictures of shitty priest, and had an obnoxious flash that was a borderline weapon, so it was his now. Well, he assumed it was expensive since the only camera he'd ever gotten to look at was a crude piece of plastic that you couldn't even preview what pictures you took and was decorated with cartoon dinosaurs. "Disposable and child-proof, perfect for you!" Yuri had chirped happily.

Needless to say, the camera soon found itself on fire without any use. Satan had ignored Yuri helpfully pointing out that if he kept it, he could have taken a picture to keep.

"Did you pay for it?"

"No, but you did give it to me. I'm not going to break it, old man, so calm the hell down." The irony of that statement was absolutely staggering, but Satan hadn't been one to care about little details.

Shiro gave a non-comital grunt, disbelief clear. But he didn't try to take the camera or anything equally foolish- he wasn't too keen on seeing several hundred dollars' worth of technology smash to bits. Instead he slunk after Rin, watching the boy practically prance around, taking pictures of anything that even somewhat interested him, and felt his heart clench every time Rin held the camera out carelessly in one hand. Seemingly happy with himself, Shiro couldn't stop Rin from turning around and darting outside.

"Yukio! Yukio, look what Shiro gave us!"

There was a worrying amount of commotion and noise, so Shiro quickly made his way outside. Rin had handed the camera off to Yukio, excitedly going over the settings he'd figured out in his short time with the device. Yukio nodded, only half understanding, and pushed a few buttons. He jumped as the flash popped open and fumbled the camera, only for Rin to nimbly catch it.

"Be careful! Cameras are fragile." Satan chided, and looked over the preview screen. There was already a scratch or two in one corner and he frowned.

Seeing his chance, Shiro stepped in, "Yes, they are very fragile, so maybe you should hand it back to me?" The twins were responsible enough, but he'd already seen one near-tragedy.

"But I like it." Satan wined, and it was surprisingly honest. He hadn't thought much of what a camera could do when he'd first seen one, but now, looking over the pictures of Yukio he'd taken, he just had to have it. He could print memories with it, of times that were slipping past him too fast.

Shiro felt his mouth go dry. Rin had never really wanted anything before, at least, not anything Shiro was willing to give him. It was always dangerous, violent, things he wanted: knives and blades of all kinds, flint and matches, there had even been a question or two about a gun of all things and he knew the watergun wasn't at all what Rin had meant. It was desperately worrying and he'd sunk a small fortune in expensive game systems and sports equipment to try and get Rin interested in something not dangerous. But the consoles say untouched and only odds and ends of any of the many balls and gloves and bats were used, with no real interest in actually playing.

There was still the matter of just how nice that camera was though, "No Rin, the camera isn't yours to keep. But, if you really like it so much, and pray the lord for strength to be a good child-"

"Ha!"

"-then maybe you'll get a camera for your birthday." Preferably something a fifth the cost.

" _A_ camera?" Satan drawled, unamused and already knowing that the shitty priest was trying to scam him.

Let it never be said that Rin was shrewd, for better or worse, Shiro mentally sighed. "This model is very expensive-"

"Not so expensive you couldn't buy it on a whim though."

"It wasn't a whim; I've needed a nice camera for a while now. Besides, you can still occasionally use this one, but you hardly need something this complicated."

"It sounds like you're being cheap. And don't trust me with nice things."

Neither of those were exactly wrong, but Shiro wasn't going to _say_ that. No, instead, "You don't even know what half these settings do, Rin. Yukio, why don't you be out model for today, ok?"

Yukio perked up at finally being included, "Ok!" The eight year old stood as still as he could, doing his absolute best to be a perfect model.

Shiro knew it could only last for so long, so he worked fast. "Look, you aren't even on the right one to take pictures outside. Change the settings with that wheel right there."

Satan obeyed, but mostly because he was curious. He hadn't really noticed a difference except the ones that made the picture worse, so he hadn't messed with them. They probably did nothing and the shitty priest was just making things up to try and convince him to give back the camera.

"No, not that one, the one to the left. And now it's to the right. Let me show you." Shiro leaned in before Rin could have a chance to object and quickly fiddled with the settings. "See? The colors are better now, richer and not as washed-out. And see, if you turn on the red eye remover, then adjust the focus…And…"

Satan was a born liar, but even he had to admit that the picture the Paladin had taken of Yukio was worlds better than anything he had. "You do know you've just made me want this camera even more, right?"

"And how do I know you won't get bored of it after a week? You've done it before with those games."

"I never asked for any of those. Besides, then you'll have a spare if _you_ ever break your camera. But that's only if I get bored of it. Which I won't." Not when the world was ever-changing unless he caught it with his own two hands. Not when it meant years of Yukio's life would slip by, only remembered as a hazy fog. The photo albums weren't nearly enough.

"I want a camera too!" Yukio suddenly exclaimed, excited. If Rin wanted one so bad, then they must be even better than he thought!

An idea struck Shiro "Well then, I can either get both you and Yukio cameras, or just you. Which will it be?"

Satan knew he was had, because he was still, forever, greedy and selfish. He didn't want to deny Yukio anything the world had to offer, but he also wanted _his own_ camera. Plus, he knew the shitty priest would never actually buy him something that nice, but he kind of wanted a reason to get mad. Besides, he could always steal it and frame it as if someone had broken in or something. "Fine."

"I'm glad that's settled." It wasn't like there was ever even a chance that Shiro would cave, but he knew being dismissive of Rin without reasoning would sour what he was desperately trying to build between them. "Now, come on, sit here."

"Why?"

"Don't you want to know what the other modes of the camera can do? I did say you can use this one, if you want."

Reluctantly, Rin sat down, looking far less pleased than an excited Yukio.

And that was how a good hour passed, sat on the steps just outside the back door and with the twins on either side, eager to learn. Yukio, despite being so enthusiastic, grew bored quickly and was clearly only still there because his brother was. Rin, however, sat with a deceptively bored expression on his face, but nothing could hide the rapt attention deep in his eyes, absorbing everything Shiro had to teach for the first time in…in a very long time.

Something swelled in Shiro's chest and he knew, deep down, that everything would work out.


	15. Echoes of the Future

Chapter 15: Echoes of the Future

Satan was undisputed tyrant of the playground. He'd climbed the ranks laughably easy- even the oh-so mighty fifth graders who towered over him by half a foot ran away crying when he barely touched them! None of the fools who'd attacked him wanted to admit that they'd been beaten up by a kid half their size and only in the third grade, so instead they plotted. Even when they'd ganged up on him like the cowards that they were after school one day, Satan hadn't even so much as twitched. Instead, he pushed Yukio behind him and stood there, as unmovable as the brick walls on either side.

Some would say he was trapped, but Satan saw things a little differently. The walls only meant his prey couldn't escape.

It should have been easy for the demon, but his body was still tiny and light without his real power. He couldn't draw out his flames and the power they brought if he didn't intend to kill the witnesses, and Yukio was behind him, terrified. So he fought, vicious and feral, tackling legs and stomping on the softer bits that left the boys in so much pain they couldn't even scream. Satan threw the obese fool thrice his size who'd tried to pin him twenty feet away and at the feet of his remaining allies like a twisted offering, and, all at once, the fighting seemed to stop.

It wasn't nearly as far as he'd have liked, and it left him tired, but it also made him feel strange…It had been too long since he'd had a good fight, ever if he had to hold back his power, even if he felt tired like this, the roaring in his ears coupled with the wannabe bullies terrified faces was positively _addicting_.

Satan's grin was bloodthirsty madness and his eyes were just a little too bright in the darkness of the side street. His flaming heart demanded sacrifice.

The ragtag group of kids, like the cowards they were, fled in terror with shrill screams.

"Monster!"

"Demon!"

Satan felt his blood rush even faster, and his grin threatened to split his face. The raw terror, the thought that fleeing would make them safe, their own hubris, all of it was mouthwatering. He lowered himself until his was half-crouched, ready to sprint after he felt his prey had enough of a head start. Maybe he'd pity the fat one lagging behind and leave him for last, darting ahead to rip apart his allies before his eyes. He'd surely have a _fantastic_ look on his stupid-

A hand, hesitant but firm, grabbed his wrist. Satan nearly torn the _fool_ in half on the spot, except-

Yukio was shaking just a bit, and refused to look into his not-brother's eyes, "Rin, that's enough."

The fight fled Satan in a rush, chased away by the thought of " _Yukio's afraid of me"_ and his body sagged, deflated. Exhaustion embraced him suddenly, and the demon could only find it in himself to nod. Suddenly he was aware of the stings of a whole plethora of cuts and scrapes and slumped a bit, gravity heavy on his body. Yukio hadn't let go of his hand and, surprisingly, took the lead and walked both of them out of the ally. Down the busy streets Satan had always hated, past that one dog that always barked at him that he hated too, and back to the church he….tolerated. Yes, tolerated only because Yukio needed food and shelter and warmth that wasn't from flames that would bring the entire world down on his head.

"Sit."

Satan sat, and, because, Yukio looked oddly intense and determined, didn't move even when the other left.

A minute later and Yukio was back, lugging a first aid kit. Then, as if nothing was different, as if he hadn't just seen something frightening in his supposed brother, he set to work. Maybe he hadn't thought anything of it, maybe Satan had already corrupted him, twisted his world view into something vile? Silent acceptance of bloodlust wasn't something Yukio should ever be forced to endure.

"Rin, your arm."

He let Yukio take over completely, trusting the boy despite how young he was. Yukio had steady hands and a good head on his shoulders and this wasn't even close to the first time he'd had to patch someone (his troublesome twin) up before. Satan watched him work, saw how unaffected by blood he was, and how he'd already memorized what everything in the first aid kit did. More and more the demon had wondered what Yukio was going to do with his life. Nothing dangerous, that was for sure, but it had to be something worth wild, something that Yuri would be proud of.

Ah, he was an idiot. The answer was playing out right before his eyes.

"You should become a doctor."

Yukio stopped, shocked and rapidly flustering, "A doctor? But to be a doctor you have to be really smart, and you have to go to a lot of really hard schools and pass a lot of tests, and be really strong-willed and with a lot of persaver, perseverance. And…and…"

"And you'd be good at it." Satan finished with a smile, waving his injured arm around, "You're already doing it now, you know! These bandages are wrapped pretty nearly, though they could be a little tighter…" He tugged on the edge of the gauze, feeling the slight looseness.

"Sorry…"

Satan lightly poked Yukio's downcast forehead, forcing him to look up, "Don't say sorry, you don't have anything to apologize for! It's not like anyone's taught you how to do any of this, but you've picked up on it anyway."

"I just do what I see dad do."

Satan only nodded and didn't try to tell Yukio to not do that, no matter how much of a bad taste it left in his mouth. The man was Paladin for a reason and had extensive knowledge on treating injuries of all kinds, so he wasn't a _bad_ indirect teacher. But he still hated letting the shitty priest treat _his_ wounds even more than he hated his body's ungodly slow healing rate that meant he actually needed to wrap his injuries. He didn't consider himself vulnerable even when he was hurt, but he hated it when the Paladin was close and could see just how easy his skin broke, how much he bled. The man always smelled faintly of gunpowder and Holy Water, and it drove the demon up a wall.

"You are right that you need to be strong willed to be any sort of doctor…" Satan knew Yukio already had underlying steel to him, a core that wouldn't ever distort as the rest of his squishy self-worth caved in. But the issue was teaching him to have confidence in himself.

The answer, to Satan, was simple, "Yukio, I'm going to finally teach you how to fight!"

"What?" Yukio jerked back, eyes wide, "What does that have to do with this!"

"Everything!" Satan decided he'd put off training for too long now. What if he hadn't been there today? "I'm going to teach you how to snap a femur and _then_ you'll be able to handle anything!"

"But I don't-!"

Satan ignored the attempted protest, "Oh you'll be fine, you'll do great at it and I know you'll like fighting! We're related after all, right?" Fighting, being the best, all of it was in Yukio's DNA. Even if it was only academically, Yukio already fought and utterly crushed his classmates.

"I don't want to break anyone though!" Yukio wasn't entirely sure what a femur was, but it sounded important. It was probably a bone if Rin talked about 'snapping' it.

"I was just exaggerating for effect, calm down." The demon ruffled Yukio's hair, snickering when the boy pulled back with a whine, "But it is about time you learn to at least defend yourself, ok? It'd make me worry less whenever you go off on your own!" Satan let just a fraction of the fears he felt every day bleed through for just a second and he saw Yukio's weak resolve break. It was low, there was no way a child could stand up to the countless worry a demon could bottle up inside, but the demon couldn't care, not when it meant he'd finally get to start training his son.

"Ok…"

"Great, we start now!"

Yukio shrieked as he was pounced on and viciously 'attacked' with tickles. Distantly he heard Rin giving tips on how to throw him off, but the younger boy was helpless to do anything but squirm.

It was like that Shiro found them, Yukio desperately trying to get away from his cackling older brother, medical supplies scattered everywhere from the scuffle.


	16. Interlude: The House of Cards

Interlude: The House of Cards

 **I keep alluding to an overarching plot I don't have any actual plans for.**

* * *

Gehenna was, without a doubt, sure to devolve into civil war within a few years. Maybe a decade if Mephisto called in every favor owed to him, but no more. Now, he was no fool and knew that the entire realm was always more or less on the brink of some sort of war, so what made this any different? The masses were always discontent with something or another and the only reason the entire world wasn't (more) on fire was, ironically, Satan. The undisputed ruler was more or less the single force keeping Gehenna as a mostly united kingdom instead of splintering into factions like it always seemed to want to. If someone decided to get the bright idea in their head that they'd be a better ruler and the fire of rebellion began to grow, Satan very quickly showed them that his flames were _much_ brighter. So, as much as Mephisto hated to admit it, Satan suddenly vanishing from the world was problematic and quickly hurtling towards catastrophic.

What was truly worrying the King of Time, however, were the circumstances around Satan's disappearance. Satan was well known to disappear for months, sometimes even years, at a time, so few knew what made this time different from the others. But Mephisto did, and it was the fact that it all had something to do with a _woman._ It seemed like an inconsequential fact to most, but he had latched onto that one detail like it was all that mattered, and was sure he knew the rough circumstances that had led to Satan's disappearance.

It was a little known fact to those outside Gehenna, but Satan rarely took any interest in any sort of female, no matter how threw themselves at him. It was fairly obvious if one simple looked at how few kids the ruler of Gehenna had despite his impressive age, and yet the Exorcists never seemed to realize how lucky they were. Logically, Satan should have had an absurd number of direct descendants, literally hundreds wasn't out of the question considering how most demons didn't die of age, and yet there weren't even a dozen running around. But the azure demon hadn't even so much as glanced at a female beyond a succubus, famous for their infertility, for several hundred years, and hadn't shown any signs of changing.

Being one of the eldest, Mephisto had seen the steady spiral his father's love life had been. And what a concept that was- a demon, the strongest demon at that, seeking love! The degree of interest he'd taken in each of his children's mothers had varied wildly, but it had one specific pattern: down. Some of the last had been, at best, a passing interest he'd totted around for a few weeks before casually discarding, not caring that they were pregnant in a typical demon way. They were effectively immortal, why would they have to care if they had someone to carry on the legacy or not? Children were an afterthought and, sometimes, competition.

But the earliest ones where the most telling, and a part of Satan's history so many demons forgot or thought unimportant. But not Mephisto, for the future was born from the day's long past. Satan had held onto the demonesses for several years in some cases, giving them more attention and care and affection that anyone who wasn't there would have thought possible. Looking back on it, Mephisto had realized that Satan had been searching for…something in those women. Something which he never actually found, and eventually he discarded those 'treasured' women as well, usually when they became pregnant and they sought to isolate themselves to protect their child. Each woman kept his interest for a shorter and shorter time, the gaps between them growing longer and longer, until he'd seemed to grow bored and stopped entirely. None of the Demon Kings had questioned it because it worked in their favor. There was no risk of competition suddenly showing up and once again disrupting the hierarchy they'd established.

And then Yuri Egin had appeared.

A woman, a human one at that, who'd completely and utterly overtake his father's life.

At first he'd simple thought it was because her body could, impossibly, withstand his flames. It would be easy for such an ancient demon to bewitch such a young woman into eventually falling under his thrall, and then he would have had a lasting body. When Mephisto had learned she was carrying not one, but two of Satan's children, he'd realized his father had decided to use her to bear him more children, possibly because he found her immunity interesting. The fact that one of them had _blue flames_ only made the accurately named Blue Night make all the more sense in hindsight: Satan had finally made a true heir, so why wouldn't he protect that child, and, indirectly, the mother?

But when it ended, with Yuri dead and Satan nowhere to be found, Mephisto realized he probably should have paid more attention to what had happened between the human and demon. Whatever it was, it was something he fundamentally couldn't understand, for his black heart simply wasn't capable of feeling that oh-so-human emotion.

Love.

Did Satan love Yuri Egin, or had he loved her ability to bear blue flamed children? Mephisto didn't know, and, while logic and Satan's own behavior would dictate that he saw her as nothing but a way to breed a powerful army, he had a feeling, rotting and hurting his head with the impossibility, that Satan had never been looking for that. No, he'd always been looking for something more, and it was possible that Yuri had shown Satan that very thing.

Mephisto knew the past well, knew why the Blue Night had occurred far better than any Exorcist did (they saw it only as a random act of violence from a demon that needed nothing to justify it, oh how wrong and hypocritical they were as they lit their torches and prayed under a burning woman) and he knew what the results had been. He knew, and yet Satan's future was still hidden from his eyes. Yuri, the woman Satan had finally loved was dead. Even with her children alive, even with one with a heart of blue flames, did that even matter to Satan? Mephisto had studied human love extensively and he'd hear of how all-consuming it could be, and the madness it brought.

So, just what sort of madness had love cursed Satan with?


	17. Tail

Chapter 16: Tail

 **Some things just aren't worth it.**

* * *

Satan didn't like haircuts. In fact, he didn't _do_ hair appointments at all.

The idea of letting anyone near his neck with anything sharp went so far against everything he'd ever known that, the first time he'd been taken to a barber shop as a baby, he'd very nearly lost it and mauled the workers there. He was so unruly that said haircut simply didn't happen for quite a while. He just _barely_ tolerated the shitty priest trimming his hair after that, and that was only lasted until he was physically able to coordinate his hands around a pair of scissors.

He had a system in place, in fact. Cutting his hair was a pain to remember to do, made even worse since his hair grew abnormally fast, so he'd really only bother keeping his bangs out of his eyes. The rest he let grow until he could be bothered to cut it, which was whenever the mood struck him. Sometimes he kept up with it, sometimes he didn't and months would pass, and he, with practiced ease, collected and tied back his longer hair once it started tickling his shoulders. It was strange, seeing his hair so dark and foreign, but the novelty wore off pretty quickly. Eventually he'd get sick of it, or it really would get too long to deal with, and he'd chop the hair off in one swift movement before practically attacking his hair with the scissors until he reached that perfect messy-neat balance that best suited the shorter locks.

Probably the most unintentional side effect was the way he drew strange looks as his hair grew long. It confused the other kids to no end to see a fellow grade-schooler who didn't fit with their still growing world-views. They didn't actually know the difference between boys and girls to the point that, when he put off his grooming long enough, plenty thought his longer hair suddenly made him a girl.

He very quickly knocked that notion right out of their heads, and even let his hair grow a bit longer just to irk the idiots. The teachers that hadn't liked him in the first place were surprisingly quiet on the whole issue. Satan was sure it was because the cowards didn't want to explain human gender dynamics to a bunch of ankle-biters who barely even knew they had different parts.

Today, however, things had gone….differently.

When he walked through the doorway, Yukio weakly trailing behind him, he brushed past the shitty priest and…strongly walked into the kitchen. He certainly did not storm, did not stomp, and was not at all huffing as he dug through the drawer and pulled out the scissors. From the corner of his eye he saw Yukio trying to shoo Shiro out, but that was hard to do when he barely came to the man's hips. The sound of a snicker was all he needed to hear to know his son had failed at the futile task.

"So, getting rid of that ponytail, Rin?"

"Yes."

Because he wanted to. Not at all because someone had stuck a fat wad of gum in it.

* * *

 **Short chapter to let everyone know I'm alive. The next one will be much longer.**


	18. Doused

Chapter 17: Doused

Logic would dictate that Satan, ruler of hell and wielder of the azure flames, would hate water above all else. It naturally countered his element, and Holy Water was an annoying common weapon among Exorcists, what with how easy it was to make with the right know-how and materials. And that logic wasn't even necessarily wrong; Satan hated getting caught in the rain, hated being splashed, hated even being near a large enough body of the stuff.

The only exception were his hour-long soaks he'd take in water so hot that the shitty priest swore up and down he was going to pass out and drown one day. Satan scoffed and ignored him, sinking up to his eyes and letting the heat seep into his bones while he did his best to also ignore the fact that he was _wet._ Instead, he focused on breathing in the steam and pretending he was wreathed in his pretty blue fames again, fire chasing out the chill that never seemed to really leave him these days.

He was just a tiny bit of a contradiction, a fire demon enjoying water. But it was only on his terms, under ideal circumstances where the water was already practically steam.

So why, _oh why,_ did the shitty priest think that he wanted to go on a trip to a _lake?_

The water in the wretched cabin was barely warm, the lake freezing even if it was suspiciously clear of minor demons, and Satan had to put Yukio's training on hold lest the Paladin of all people object to teaching (demonic) self-defense. The man would probably insist on watered-down human classes instead, and Satan wouldn't dare hand the safety of his child to anyone else. The sudden absence of the wards he'd grown used to sleeping under, pricking at his skin like an annoying reassurance, made him restless, even if the cabin itself was well protected relative to its size. He hadn't slept well the first two nights, the scent of weak demons in the surrounding forests taunting him. It was only after he'd snuck out and carved out his own territory via murder that he felt it was even remotely safe for Yukio.

Overall, he was miserable and in an even worse mood than usual. Satan had been in the lake exactly once in nearly seventy-two hours (only to make Yukio feel better, like this wasn't a _terrible_ way to waste his time) and spent most of his time sprawled out on a towel on the grass, lazily keeping an eye on Yukio. It meant he wasn't as close to Yukio just in case something went wrong, but if he thought the shitty priest would let the boy drown for even a second then no one even would _be_ in the lake. Besides, Satan was pretty confident in his sprinting abilities; he had plenty of practice chasing down prey, so getting from point A to B even when starting sprawled on his back wasn't an issue.

Besides, Yukio was _finally_ getting old enough to actually look after himself somewhat. Sure eleven still meant puberty was a year or two away, but he could trust his child to not wonder off with what few bad people where left in his city. Hmm, he might have to change his tactics, since he couldn't pull off 'cute and ignorant child' that well anymore. Satan sighed and stretched out further from his place on the grass, feeling warm and lazy and could strongly empathize with any cat now. He'd figure it out later.

A creature abruptly darted up to Satan, inches from his nose, faintly shining. It was a pretty little thing barely a foot tall, with bright dragonfly wings and big, glassy, blue eyes. Its vaguely human body shimmered from the tiny, crystalline feathers that took the place of human hair and decorated its arms and legs like fins. The effect was dazzling and mesmerizing as it darted through the air nimbly, to and fro, catching the light off its jeweled body. Happily, it gestured for him to follow it, its voice a ringing bell to sooth the soul.

Satan was unimpressed- faeries were always annoying creatures. Oh sure, some humans were enchanted by their beauty, but they were spirits, demons, all the same. Just because humans now lived surrounded by iron, they suddenly forgot of the numerous changeling children and other ills.

" _Come with me, child, I have much to show you!"_ It chimed, musically, even though a human wouldn't be able to understand it. It probably liked the sound of its own voice, the vain little thing.

Satan grumbled, eyeing its wings with just a touch of envy and longing, "Go away, you're annoying me."

" _Come already, child! Follow me before the Exorcist looks this way!"_

And let the faeries waiting try and possess his body? As if he was as stupid as their usual prey! Not that it'd ever work, even less so since he was naturally immune any and all charms (well, with _one_ exception, because even if Yuri swore it wasn't magic, Satan _knew_ better), but it'd be a waste of both their time and make his life a hassle. Probably because he'd have to track down every damn faerie and kill them all. No, he'd rather soak up the sun and enjoy the quiet that being away from the busy city brought. He might as well get something from this shitty trip.

Satan rolled away and lazily swatted the annoying fly.

" _Get up, don't you care that there's a faerie here? You should!"_

Not in particular. "You're fucking annoying, scram before I kill you."

" _Such a rude child, you're so much worse than the other! Oh well, it's not a complete loss. It'll be easy enough to separate you when the Exorcists go searching anyway."_

Go searching? What was the damn thing yapping about-

" _I'll see you soon, wretched chilAH-"_

The faerie's screeching ended as soon as it began, Satan's hand crushing and burning its fragile body to ash. He didn't take time to examine his work or admire his flame, throwing the crumbled thing to the wind and taking off at a dead sprint as if his life depended on it. In a way it did, for Yukio was nowhere to be seen and Yukio was _his world_. He was so stupid to not realize just how dangerous fairies could be to someone who wasn't immune to charms, and he'd been the very one who'd been trying to tell Yukio to be less afraid!

The _piece of shit_ priest and his lackeys, only just now noticing that Yukio had gone missing, called out after him and his mad dash to the tree line. Satan didn't dare stop, didn't even slow, but he did shout back at them.

"Faeries!"

Satan, however mocked he was, trusted that the man was the Paladin for a reason and could understand what that meant and wouldn't waste time trying to question him now. How 'Rin' knew what fairies were could come later, and he felt his confidence soar as the sound of feet crashing through the forest with no calls to stop rang out behind him, only to slow down. Satan ignored them, just like he ignored the pain in his bare feet and the gnawing hole in his heart that threatened to swallow him and the world if Yukio was even so much as scratched. Instead, he trusted his primal instincts, catching Yukio's scent and chasing it down with unnatural speed.

Satan tore through a bramble bush without even slowing down and barely remembering to protect his fragile human eyes. Thorns and twigs ripped apart his skin, but he couldn't even pretend to care. A blood trail would make it easier for the piece of shit priest to follow him, and pain was something that didn't even matter, no matter how young he was supposed to be. Physical sensations were temporary and easy to block, he could understand and process and overcome them infinitely better than the screaming in his heart.

Appearances could go and _burn_ if they in any way, shape, or form put Yukio in danger. He'd burn the entire fucking forest down, consequences be damned if that was what it took

* * *

In the end, Satan's worry was unneeded. Yukio, by virtue of either his own intelligence or the traces of demon blood in his veins, had broken free of the faerie's charms. He knew this because he practically trampled over the fleeing and terrified child, a swarm of lights chasing him. Satan barely slowed, sweeping Yukio up into a crushing embrace and spinning dizzily with momentum.

"Yukio! Yukio, Yukio, you're alright, you worried me so much! I should have realized something was wrong when I saw a faerie, no, I should have checked the forest more thoroughly! I'm sorry, are you ok, are they still trying to charm you? Don't listen to them, I'm all that matters, ok? Ok?" Satan knew he was rambling; sinking to the forest floor as his knees failed him from the sheer _relief_. He'd almost failed Yuri again (again, again, always again, _it was always, alwaysalways-!)_ and if he hadn't been so deliriously happy he would have killed the lights that buzzed angrily around them, voices screeching bells. His sweeping flames could have cleansed the woods of such low level demons without even scorching the barks. He'd have to break the seal for that sort of power and control, but if he hadn't been so stupid, hadn't gotten so complacent and comfortable-!

"Are you hurt, did they do anything to you?"

( _He was always failing when it mattered.)_

"Rin, they're still there! Right behind you!" Yukio, beautiful child who cared so much for others (so much like Yuri, _Yuri_ ), sobbed, torn between hiding away in his twin's arms and trying to pull back and keep running. Satan just huffed, running his hands through Yukio's soft hair and reveling in the fact that he was still there, still _hishishis-_

He let Yukio's scent, his simple existence, wash away the madness for another moment.

"Ignore the stupid faeries, they don't matter anymore now that I'm here, ok?" Not when he was so much better than them, so far beyond them until they were nothing but the very insects they resembled. Oh he'd kill them, burn them until they were actually _dead_ , for what they'd done, but he had things more important than swatting pests to take care of first. Yukio was shaking almost uncontrollably, seconds from sobbing, so Satan pulled him close and let his warmth envelop and reassure _his child_ ( _his, his always, his only real-)_ that he was _here_. He'd kill anything that ever frightened him again, and he would have whispered such sweet promises of revenge to Yukio if he had the time.

The sound of fatal verses being chanted was hardly Satan's first indication that the useless humans had finally caught up. Hyper-aware of his surroundings and the dozens of faeries that circled _his child_ like vultures, the Exorcists' noisy, and late, approach was as obvious as the crack of thunder. The faeries scattered, a few of their number dropping from the sky, bodies suddenly soulless, and crashed almost soundlessly into the bramble around them.

Satan let them go.

They would live for now, because, he knew from the grave look on the Paladin's face, that he had more important things to take care of. The first lie would have to fall apart, years of effort gone in an instant. But Satan couldn't regret a single thing, even as he slowly stood, never breaking eye contact with the Exorcist. Not even Yukio's gasp at the sight of his bloodied legs and arms could make the demon doubt his choices.

He didn't have room in his heart for yet another regret, after all.


	19. Hot Coals

Chapter 18: Hot Coals

 **Continuation of "Doused". Finally forced this chapter out so I can actually continue to story.**

"So, how long?" Shiro finally asked after nearly thirty minutes, when the bowl was full of thorns and spurs and Satan's legs were covered in bandages and stinging disinfectant.

Satan hummed and entertained the thought of pretending to not understand the vague question. But no, Yukio had just left the room to get more towels, and if he needed to take drastic action then he would rather do it without further traumatizing his son, "How long do you think?

"Long enough to know what faeries are."

Well that was a fair point, and pretty incriminating too. But Satan had one to match, "I didn't really know what the bastards looked like before today, I just guessed. They aren't exactly hard to identify, what with the wings. Anything that gets its sick fucking kicks out of kidnapping children is something I memorized, just in case it's actually real."

His voice dropped to a low growl, and he itched to burn the entire forest down just to be sure he killed them all. How dare they think themselves so superior as to try and even look at, much less _kidnap_ his child. He would kill them all beyond dead, remind them of why the blue flames were so feared as he burned their existence into less than the nothing they already were, reduced to ash they could never come back from, but only after they suffered and _screamed in a wash ofazurefireflamesblazeinfernopu-._ The seal strained to hold the fire slowly eating at it, and for a moment Satan felt his inner warmth return.

With ease born of practice, he let go of his power and anger. "As for how long, well, for as long as I can remember. It wasn't hard to realize no one else saw those things, and you never seemed to react to them, so I kept my mouth shut." He looked away, a bitter, self-hating mask slipping onto his face, "I'm already enough of a problem child, don't want to add crazy to that list, eh?"

Shiro made a noise of acknowledgement, and pulled out the very last thorn thorn. The silence stretched awkwardly, until Satan huffed, "Hey, you were supposed to deny that 'problem child' part, you know."

"And why would I sin and lie?" Shiro said casually, and his lips twitched at the indignant squawk Rin made, "Besides, acknowledging a problem is the first step to fixing it."

If it was a fight the shitty priest wanted, it was a fight he would get, and Satan loved verbal fights almost as much as physical ones, "Just like how you've completely, one-hundred percent acknowledged that you've become the bane of society: a perverted old man?"

"You're pretty snarky today, aren't you?"

Check and mate. "And you're pretty damn careless today, letting Yukio disappear like that."

Shiro, to his credit, didn't flinch like Satan had been hoping he would. But his hands stilled mid-motion to wrap a final layer of gauze around his torn ankles. It was much subtler, but Satan heard the slight intake of air, saw the way the man's eyes clouded over, and he knew he had won, even as Shiro gave protest, "He just wanted to get something from inside the cabin. I didn't think anything could happen, not after I warded and cleansed the area."

"Yeah, well, assumptions are how kids get kidnapped by faeries."

Shiro did flinch at that. Only a little bit, but he still flinched.

Satan didn't feel nearly as happy about that as he thought he would.

"It seems I've been…remiss in my duties to educate you two. Even if I thought neither of you could see, it would have been for the best to teach you how to survive the demons."

"Yeah, it would have." Satan agreed, mocking but with less bite than he normally could muster, "But most demons don't really bother you if you don't bother them first, so it's not like you'll have to teach us that much."

"Demons are dangerous."

Platitudes and platitudes, and yet the man had willingly raised two, Satan noted idly. Granted, it was probably some pathetic human regret driving his actions, but he tried more than he had to, and he cared more than he had any right to. Besides, "Only if you piss them off first, usually. Unless they're an asshole, but that's the exception. It's humans that go out of their way to fuck with your life, you know."

"Rin-"

"Bullies, kidnappers, mob bosses, drug attics, rapists, murderers, cultists, idiots with nothing better to do, the list goes on and on." Shouting, screaming, chanting and praying, red fire that burned, wash itaw _aywithcleanblue-_ "There's a lot of people out there who would want to hurt little kids for no real reason other than that they _can_."

He had thought about this for a while, and, as much as he hated it, it was the best plan he could come up with. Yukio would never be as strong as a normal demon, not while he was so tragically human, and not when he preferred books to fighting, healing to hurting. And so…

 _Andsonoonecouldhurthisagain-_

"Teach Yukio how to use a gun. I've seen them around the place, and I know you brought at least two with you, 'just in case' right? So teach him, because Yukio isn't ever going to be a fighter like me."

Satan had expected a lot of things to happen after his made his demands known. He had expected shouting, anger, or outright refusal. And so, he had a response for each, a way to lead the conversation until he got what he wanted. The road didn't matter, for the outcome was already determined.

"I would have done that even if you hadn't just done your best into guilting me into it."

That was an unexpected response, and not a pleasant one, even if it made Satan's life easier. That implied the Paladin thought they needed protection, which meant…what exactly? "…Why?"

"You and Yukio are almost ten now." Shiro continued, more to himself than anything, "That's still too young, but it'll have to do."

Shiro could tell that Rin was a half second from demanding answers, but-

"Dad, I brought more towels. Are all the thorns out?"

-Yukio walked into the room, arms burdened with tacky beach towels and Rin's mouth slowly closed.

"Yes, we just finished up. Put the towels over on the table and sit down. I have something important to tell you and Rin." Shiro asked, glad he could focus on Yukio and turn away from Rin's too-intense gaze for a moment to gather his wits.

Shiro didn't want to do this, not when he knew the names Rin had suffered and the lengths Yukio went. They had suffered together already, each responding to abuse in their own, unhealthy, way. No child, no matter how tough they acted or thought themselves, should know what he was about to tell them. But…

 _The letter was short, unremarkable, and cryptic, but it still threatened to shatter his world:_

' _Gehenna has grown restless without its azure king.'_

…But he didn't have the luxury of hiding the world from them any longer.

"Dad, why do you look so…" The word 'serious' was on the tip of Yukio's tongue, but that didn't seem like enough. Not when his father, always light-hearted and smiling, looked ready to go into a hopeless battle like a hero from the shows he watched.

"Rin, Yukio, I'm sorry, but there's been something I haven't told you. I wanted to wait until you were much older, but things have changed. No matter what happens, I'm going to teach you about the demons you two can see, but I need to tell you something important beforehand. So what you learn won't color your opinions."

Shiro took a moment to breath in deeply and prepare himself. He closed his eyes for just a moment, and so he never saw how Rin's eyes widened with a revelation. A revelation carefully suppressed before the thought had even fully formed.

"I've never really told you about your parents before, your real, biological, parents."

When it was clear no one else would continue, Yukio tentatively muttered, "You said out mom was really brave, but really kind too. And that she fell in love with a bad man who tricked her."

If his acting didn't need to be prefect right now, Satan would have laughed at how perfectly backwards that summary was. But that was the only narrative a human could ever entertain, so he let it pass.

"Yes, your mother, for all her mistakes, was nothing if not the most honest person I've ever met. She was honest with everyone, especially herself, even when it was painful. A lot of people didn't like that about her, but that's what made her so special. Because she could accept the truth, she could live her life as she wanted, no matter what others tried to say."

Yukio made a confused face, though his question was a bit of a surprise. "What's so special about being honest with yourself?"

Before the shitty priest could open his mouth, Satan cut in. This was _his_ territory, his own experiences, not some asshole who could never understand what it meant to have your world so lovingly taken apart. "As you get older, it gets…harder to admit when you're wrong, or don't know something. Or maybe you don't like something about yourself, like being lazy or scared of something, so you pretend you aren't that thing. Most people don't even realize they're doing it."

"I see." Yukio nodded seriously, not seeing how Shiro was staring at Satan as if he had grown a second head. He didn't understand, but that was fine. Yukio was too honest, too hungry for knowledge, to understand what it meant to lie for years and years to yourself. "And what about our dad? Why was he a bad person? Was he in the mob?"

It was such an innocent guess that Shiro almost managed a laugh around the rock sitting in his chest. Almost.

"If only it were that simple. No, he wasn't. Your father was a demon."

* * *

Out of all the reactions he had expected, Shiro still hadn't been mentally prepared enough (he never was) for the fallout. Rin had only looked vaguely surprised, as if he has always known he was something not-human, but Yukio…Yukio had reacted violently. The screaming, the shouting, it had all been things he had learned to expected from the explosive Rin, not Yukio, who always turned inward instead of lashing out. But maybe he should have expected it, when he knew what other children called Rin at school, and the fights that had resulted. Maybe Rin didn't care that he was a demon child because that was what he'd been labeled by society. But Yukio…

" _You're lying, you're lying! Rin isn't a demon! He isn't!"_

…Yukio had always tried to defend his brother however he could.

Yukio had run away, Rin obviously behind him, and the two were out of the cabin before Shiro had even gotten up. It was only because his associates hadn't taken off for the tree line that Shiro took his time following. They knew what was about to happen and the likely results, and even if the twins had traded expected reactions, it was still the same.

"That bad?" One of the Exorcists gathered by the door asked absently, though Shiro didn't respond with more than a grunt, too focused on locating the twins.

It wasn't hard, for out on the soft grass, Rin was already comforting Yukio. With an uncanny sixth-sense, Rin looked over his shoulder for a moment and glared viciously at the small gaggle of Exorcists by the open cabin door before turning back to the collapsed form of his brother. Shiro couldn't hear what they were saying, but knew that he would be welcome only when Rin deemed it so, and not a moment before. Otherwise the boy would be impossible to talk to, either freely spewing swears or talking in circles.

"What should we do?"

Shiro caught sight of bits of gauze and bandages peppering the grass.

He sighed.

"Find some more gauze for Rin's legs; that running probably opened the wounds. And re-ward the cabin. I don't have the mental fortitude needed if anyone tries to make a surprise visit."


	20. Study

Chapter 19: Study

 **It might be a contradiction, it might not be wise to let this happen, but Satan can't ever say no.**

Rin's grades were decidedly…middle of the road. Painfully average. There was nothing wrong with them, but where he had once been dominating every class he took, now his A's had slipped to mostly B's and some C's. Math was rapidly becoming more and more of a struggle simply because it Rin was easy to frustrate and science that wasn't anatomy related (when and how Rin had already memorized the bones and major muscles in the human body, Yukio didn't know and didn't think about too hard) practically lulled him to sleep. Literature was only slightly better, but Rin was terrible at expressing himself in general, so any papers he wrote fell apart mid-paragraph into unrelated ramblings. There was one bright spot-

"Hey Yukio, your tenses switch right…here. See? It's all supposed to be past."

-Which just so happened to be Yukio's main weakness: foreign languages. Yes, languages, for Rin had taken both German and Chinese in the same year, and was, somehow, absolutely breezing through the class. Yukio had only taken Chinese to fill his requirements, thinking he'd be easy due to the roots his language shared with it. But no, they were similar, yes, but just different enough that he kept mixing them up.

"Thank you, Rin."

How Rin kept at least three different languages straight in his head was a complete mystery to Yukio, but then again, Rin had said the same thing about Yukio and math equations just a week ago.

Rin sighed, flying through his homework with such careless speed that Yukio would normally have been worried he was filling in random answers. But no, Rin had never scored under a 95 in any foreign language course he'd taken.

The older twin sighed again, much more dramatically this time as he finished. "Do you think that they'll let me take the test soon? I'd like to study something I don't know."

It was a test that native speakers took to prove they didn't need to take the course, and Yukio had never really understood how his brother… "But you failed the last one, Rin. Somehow you ended up using really old dialects. How did you even do that?"

"Just because they were old, doesn't mean my answers were wrong! It's bullshit they failed me, and everyone knows it!"

With how Rin had apparently cussed out his Chinese teacher over some technicality on his homework last week, Yukio was sure that the entire _school_ knew now. And several Chinses slurs involving one's mother, a chicken, and something about incest.

"Yes, everyone knows now. But why did you use old dialects again? And when did you even have time to learn entire languages?"

"Trade secret."

And that was all Yukio knew he'd get out of his brother. One day he'd figure it out, but obviously not anytime soon.

"But you never _study._ " Yukio commented, and no, he did not _whine_. He was just frustrated.

Satan shrugged, not having an answer for that, "Hey, I've already finished studying for that French test, which counts for something, right?"

Technically he hadn't studied at all, but Satan was of the mindset that you didn't study something you already knew. Human languages were easy; they were all basically the same when you got down to the bare bones, and Satan had made a point to learn a new one if someone even remotely important in his makeshift court took even cursory interest in it, though he was careful to be subtle. It made his life a lot easier if he found out someone thought they were going to be cute and write their oh-so-secret plans in a human language they assumed he didn't know, even though they _kept using words of it for no reason_ and somehow thought he wouldn't think that was something worth looking into. Sure, he wasn't the a genius, but did his own subjects really think he hadn't learned a lot of things in the war he had practically single-handedly waged against Gehenna?

Idiots.

Some days Satan wondered just how much his conquering of Gehenna was him just being amazing and how much was just the fact that most demons couldn't plan their way out of a paper bag. Not because they weren't smart, but because they assumed the paper bag was inferior to them in every way and couldn't ever do anything to stop them. And so they would suffocate without even knowing it.

"Yes, but how did you first learn them?"

"I told you, I study." Today, yesterday, two hundred years ago, did it really matter when he studied so long as he did it? "Besides, it's not like you really _need_ it. Just focus on the classes that actually matter for you, ok?"

"But if I want to get into a good school, I need to have good grades overall, not just in a couple of classes, Rin!"

"Yukio."

But Yukio couldn't stop, all of his frustration rushing to the forefront of his mind, "And there are scholarships for being fluent in several languages, and that's not even counting just how useful it is to be multilingual. A lot of patients might not be able to properly communicate what's wrong with them in their second language, so if I can just-"

"Yukio, stop!" Satan snapped, voice full of the ancient authority he carried. Yukio, just a small child barely twelve years old, instantly quieted in instinctive respect. "Yukio, you'll be _fine_. You'll learn everything you need to about how to be a doctor, you'll pick up a couple of languages, and you'll find some linguist to cover what you don't know, ok? There's no way wherever you work won't have someone on-call."

"But what about in the field…" Yukio trailed off, and saw Rin's frown. He knew Rin didn't like the idea of him being a field-doctor for Exorcists, but their father had mentioned how there was a shortage of them, and he hadn't been able to get the idea off his mind since.

Yukio as an exorcist…it was a strange thought in Satan's mind. Yukio could do whatever he wanted, Yukio could do anything he pleased, but the thought of his son fighting demons when Yuri had done anything but…No, Satan denied it, even if the training would be useful when his child was targeted simply for existing, but slaughter was unacceptable. And so he guided, until Yukio had decided to be a Doctor before anything else. Yes, a healer, for that was something that Yuri would have approved of.

Maybe one day he'd let the shitty priest teach Yukio the basics of shooting, but for now hand-to-hand was enough.

"Ok, first of all, you're assuming you'll ever be on a team where there isn't a common language. Which would be dumb and basically suicidal since communication is key when fighting." Satan started, remember how many times he'd had that little lesson beaten into him, "And second, I already said you'll have someone! You're the medic, so someone needs to protect you anyway, and like hell I'm letting you go out into the field on your own anyway!"

Yukio laughed, "Well, you do always need a medic to patch you up. So of course, I have to become a Doctor, if only to keep you alive. Besides, you usually scare away demons without them doing anything."

"I told you, demons are just like bullies: most of them will put on a huge show about being tougher than you, but just hold your ground and they'll turn tail and run! And you should let them, because cornered dogs bite, Yukio." Satan recited, happy when Yukio nodded on, attentive even when it was just review. The idea of Yukio killing a helpless goblin left a bitter state in his mouth. It wasn't revulsion at the act, but the thought of Yuri cuddling with them, unafraid and warm. "Just remember that the actually dangerous ones are the ones that don't try shout and bark at you."

"Right, I won't go picking fights like my oh-so responsible big brother does."

One beat, then two. On the third Satan _moved_ and flipped Yukio, pinning his arms behind his back in a classic police-hold he had looked up on the internet. Yukio squealed and bucked and shouted, Satan laughing manically the whole time. But either Satan wasn't as good at the hold as he thought, or Yukio had a natural talent of breaking free, because suddenly he lost his grip and Yukio punched him square in the throat. Satan, of course, retaliated.

When Shiro rushed in, he nearly had a heart attack at the amount of blood smearing the floor, Yukio sheepishly stopping mid-motion, trying to shove what looked like half a tissue box up his twin's nose. Satan, however, was on cloud 9, grinning like a loon over just how much stronger Yukio had gotten in such a short time. He was pretty sure his nose was at least fractured!

He told as much to the shitty priest, and got a strong smack to the back of the head for his trouble.

"Stop rubbing off on your brother already."

"Never!"


	21. Deteriorate

Chapter 20: Deteriorate

 **Satan realizes his general foresight skills have deteriorated over the years, but that's fine because he can adapt. Mostly.**

 **AKA: the chapter everyone has been waiting for.**

The day it all went wrong came much earlier than Satan expected. He thought he would have had about two decades to prepare himself, but instead he barely got thirteen years.

He and Yukio were walking home from school, both in exceptionally high spirits despite the slight nip in the air as the seasons sluggishly changed. Satan had finally been allowed to borrow the nicer camera whenever he wished, and he took great advantage of that. He must have taken fifty pictures of the newly bloomed flowers and Yukio. Bygone were the days where he could bastardize a flower crown and force Yukio to wear it, all the while sighing, remembering how Yuri kept wearing the blasted things specifically because it annoyed him. A real shame since he got a nasty stink-eye whenever he tried to sneak one, but that just meant he had to get creative.

Shaking a tree branch and showering Yukio in petals worked well enough.

Yukio had sputtered angrily and thrown flowers in Satan's hair in retaliation.

Satan had just hummed and arranged a couple he liked so they'd stay in place and grinned with Yukio had huffed over his _lack_ of annoyance. Sometimes, the best retaliation was to show you weren't bothered, and he'd taken a liking to fragile things over the years. Beautiful and soft like feathers, they lived such short but bright lives, and were the epitome of the transient nature of the human's world. Besides, they smelled nice and nostalgic.

The flowers couldn't ever hope to block out the raw smell of _rot_ that hit him like a truck.

The sudden power stopped him short at the sheer audacity of it. _This is my territory_ it screamed, aggressive and claiming to any who could listen, and Satan's hackles rose instinctively at the challenge. He'd destroy whatever demon had decided to move here, how dare they, this place was his _hishishis, no one wasallowednearYukio_ and blue flames flickered between his fingers like a snake, his own power hissing and spitting angrily. His own aura lashed out, pushing the violating power away from him and his-

Yukio walked into his back with a shocked gasp, and the spell was broken. Satan closed his hands and crushed his fire and his raging heart alike. But the rot was still there, flooding the space his own power had aggressively burned away and oh no-!

Yukio braced himself, dizzy all of a sudden, and, with obvious concern, "Rin, what wrommh?!"

A hand over Yukio's mouth muffled the boy as Satan practically sprinted into an alley with superhuman speed, but not fast enough. Satan had picked the possessed man out in the crowd immediately, a slick businessman with an air of professionalism and coal tars about him. And, even as he did his best to hide, he made direct eye contact with the man who'd turned unnaturally fast towards the power that had responded to the challenge he'd been broadcasting loud and clear.

The smile was feral and full of too-sharp teeth.

Shit, shit! The air was sour with the smell of rot and sickness so potent he realized wasn't some lowly ghoul now. Satan was sure that was Astaroth and all he could wonder was what the actual _fuck_ one of his kids was doing here. This should be a well-known no-go zone for any powerful demons, patrolled quite literally religiously by high-level exorcists and Satan himself, who, collectively, picked off some ninety-five of all demons higher than a hobgoblin. Astaroth would be swarmed within a week and lose his body unceremoniously, so what was he doing here? There was nothing important here as far as anyone knew!

Ah, except for Satan himself of course. But he killed any demon or human who saw his fire, so how would anyone know?

Satan could figure that part out later, and instead drug Yukio further down the alleyway into a full-sprint. Yukio, always such a good child, didn't hesitate and followed without a word of hesitation, trusting him so _so_ much. They ran until Yukio was heaving, and then kept going at a jog, weaving through the alleyways Satan knew well from his hunts for demons and depraved humans alike. He made sure to take a somewhat random route, and yet always continue in the general direction of the monastery. He couldn't kill Astaroth like some low-breed ghoul, no matter how much of an idiot he was, he was still Satan's child.

Damn it.

Well, the worst the shitty priest could do was exorcise Astaroth, and that had the added benefit of no one questioning his place in the world. Plus it'd hurt like shit, and hopefully get the message across to never come back. Probably not, since Satan had a sinking feeling that he knew why the asshole was here in the first place.

A Great Dane ghoul practically as tall as Satan while still on all fours skidded around the corner and snapped angrily at them, lunging for Yukio and ok, _no._ Satan went low with a switchblade he always kept on hand and threw his weight against the massive dog, digging the blade into its soft stomach just below the ribs. The two crashed to the ground, a mess of limbs and snapping teeth that Satan held back with his elbow in its throat. He didn't stop though, and drew another knife from his pocket, this one thicker, sturdier, and stabbed viciously at the ghoul's spine and severing it easily with his strength. That knife was a lost cause, wedged between bone, so he pulled his switchblade free with a vicious twist, shredding most of its abdominal muscles in the process, and leapt back.

The smell of gore and rotting blood filled his senses, and Satan breathed the sickening smell in deeply.

The ghoul growled and snapped angrily, but even it couldn't move a body that wasn't properly connected anymore. And those wounds wouldn't be healing anytime soon, not with the Holy Water he'd coated his blades in.

"Come on, Yukio!" Satan says, turning to check on his charge-

Astaroth held the young boy still with nothing more than a rough hand on his shoulder and claws digging through cloth and into flesh. The grip tightened ominous and Yukio gasped, voice pitching high with pain, "Rin…!"

"Such strength, such ruthlessness, and that aura I felt earlier!" Astaroth practically gushed, hardly caring for the other boy in his grasp as anything more than a useful hostage. He had eyes only for the other twin, and his excitement let his disguise slip more, horns peaking from his skull as Coal Tars swarmed him happily, "Yes, even without the flames, I'm sure of it! You're a demon's child, aren't you?"

Satan barely heard the words, eyes locked onto the hand that threatened to powder Yukio's shoulder. "Let go of Yukio."

"You have the flames, don't you?" The demon king continues, as if Satan hadn't just spat an order with a detached hate, "You must, or else there's no reason father would have gone so far to protect you. Ah yes, I haven't introduced myself I've been chasing rumors for months now, and to think that you'd be here, carving out your territory in an Exorcist infested town."

Yukio whimpers as the grip tightens and his green shirt begins to turn a dark red, his thick jacket doing nothing to protect him. Satan's vision is narrowing, blood rushing and mind filled with such heady static he can feel his thoughts slipping away to a bloodlust.

"Rumors? What do you mean by rumors?" Satan asked slowly, swallowing his soiled heart down, keeping steady eye contact with Astaroth. Out of the corner of his eye, he could see Yukio moving, slowly, carefully, reaching for a pouch on his bag while still in the demon's grip, in spite of the pain.

"You've been carving out your own territory under those Exorcist's noses, haven't you, young prince? Something has been killing demons in this town for a while now, actually killing them as if they were mortals. Maybe you don't understand, but killing a demon for good almost never happens, and only the flames of our father, Lord Satan, can do that with ease!" Astaroth is more demon than human now, a sharp grin nearly splitting his face in half. "And Coal Tars see everything. Even if they can't talk, together enough of them can get a message across well enough."

"You don't say…" Satan drawls, knowing Yukio is giving him a _look_. And ok, sure, he might have messed up, but he didn't think that a few random scavengers who happened to see him hunting creeps would be missed! Or the aggressive ones he decided were just too dangerous to even be in the same city as Yukio. And those few who he'd gotten pissed off at enough to let his flames flicker, and then he couldn't just let them go…

Well, shit.

Ok, so maybe he had killed more than a _few_ demons.

"My name is Astaroth, your brother. Show me that fire, young prince. Give me the proof I need, and we'll leave this world behind and take you to your destiny to be a king!"

Satan looked dully at Astaroth, forcing his emotions away so he could deal with the here and now, and not flights of fancy ( _"You should talk to them." She said, as if it were that simple-_ ) and let out an overdramatic huff. "Interesting offer, and I'd really consider it, I really would, if it weren't for one thing."

"And that is?" Astaroth askes with baited breath, ready to rip the entire world to shreds if it would get his 'younger brother' to come quietly.

"I don't have any fire powers."

"Impossible, you have to be a true heir! Your demonic aura, your raw strength, none of it's human! I felt those flames early myself! No matter how weak they were, they existed! So, you must be the thing our father, Lord Satan, burned those damned Exorcists for all those years ago! Even your age would match the date of the Blue Night!" Astaroth ranted, words vomiting forth like disgusting froth and spilling more ugly things Satan didn't want to hear.

"There had to be a reason Lord Satan would vanish, and it must because he finally produced a true heir!"

Satan's flat expression never falters, even knowing he should technically be asking things like what the Blue Night was, "You're really reaching there. And, one more thing…"

He tosses the switchblade up and down blindly, not caring if he catches it by hilt or blade. The shoddy coating of Holy Water wore off the moment he tainted it with a demon's blood, so it couldn't hurt him badly even if he missed. But it was shiny and caught the dim light, and he could throw it at any moment, forcing Astaroth to pay attention to him and only him.

Perfect.

"How do you know it's even me? I have a twin you know."

"A…twin…?"

Yukio stabbed Astaroth in the leg.

The demon howled and lurched back with a hissing growl. Drawing himself low, his power flared angrily, muscles bulging, horns elongating and his skin darkening with his rage. Those brats, how dare they play him for a fool! He would kill them! Astaroth reached with clawed hands towards his defiant hostage - shaking like a leaf and barely gripping his knife, the weakling! – intent on ripping that hand that clutched the blade clean off-

A backpack, fat and heavy with books, slams into the demon, knocking off balance in surprise. The young prince was suddenly between the two, a small black…tube in hand and pointed steadily at him as if it were a weapon. But it wasn't a gun, there was no barrel, so just what-?

Satan pepper sprayed Astaroth in the face.

It was a perfect shot: directly into wide eyes too confused to know to defend, and the reaction was glorious. Astaroth shouted, throwing himself away from the pain and clawing at his eyes. But he couldn't escape the pain, the rubbing only pushing more spray into his eyes and making it worse and worse-!

"You _motherfucking_ , shit-eating brat-!"

"Come on Yukio." Satan whispered through a snicker, pocketing his new favorite toy and leaving Astaroth to wallow in his suffering.

"When did you get pepper spray?!" Yukio hissed, following Rin over a chain-link fence.

"Some asshole tried to use it on me, so I use it on him. It seemed to work, so I kept it. I didn't think it'd be that effective on a demon, huh…" It was probably more the just how unexpected it was than anything else, but Satan wasn't going to question his luck. Astaroth was a tough kid, he'd get over it.

An inhuman roar born from hell's deepest rage some distance behind them sent birds scattering ominously.

Satan rolled his eyes. What a damn wuss, you would think Satan had broken his tail or something.

"So, 'carving out your own territory', huh?" Yukio asks like an angry mother when they pause at the mouth of the alleyway to arrange their clothing to look a bit more presentable.

"They might have hurt you one day." Satan says, and even if it's a terrible excuse, Yukio knows him well enough to just sigh and hand over his messenger bag since Satan had sacrificed his own backpack for the greater good. It's very clear that Yukio is going to interrogate him later, but at least the boy has enough sense to know that something like that can wait until they aren't being hunted down.

Satan ends up wearing his jacket inside out, messenger bag awkwardly positioned in front of his legs, since that's the only way to not look like he hasn't just murdered something with all the blood. Yukio grimaces and zips up his own jacket to hide his own blood, and for once Satan curses the fact that he insisted on carrying the bulk of their supplies to and from school. He wants to stop and force Yukio to sit so he can tie up the wound, but they don't have the time, nor the supplies.

It is a surprisingly uneventful speed-walk to the monastery. Their arrival, is less so.


	22. Crumble

Chapter 21: Crumble

Satan slams the doors open, very nearly hitting one of Shiro's lackeys with how violently he storms in. They're cleaning and being generally useless because somehow a fucking Demon King manages to sneak into their territory and went unnoticed, so Satan doesn't even bother to acknowledge them. They fret over Yukio when he practically collapses in the pews, but Satan ignores them, knowing his child can direct even brainless fools such as them.

Satan marches directly up to the piece of shit priest, shrugging off the bag and jacket and watching him recoil at the sight of so much blood, "Oh hey there, how are you? I'm fine. My day was fucking fantastic; Yukio and I bumped into some family today. Why didn't you tell Yukio and I we had family visiting? Was it the horns? I bet it was the horns, right?"

"Rin, what are you…"

"Bastard, the fact that you don't even know what I'm talking about just proves my point! Want to fucking explain to be why you let a damn demon like Astaroth roam around this city like he owns the place?"

Someone behind him drops something that sounds breakable, but the two males ignore it. Satan, because he frankly couldn't care, and Shiro because he's so shocked he might as well have just been stabbed in the back.

"Astaroth…"

"Yeah, possessing some businessman and getting his shits and giggles by trying to rip Yukio's arm off! What the fuck were you doing here, sitting on your ass when he's out there!?"

"Rin, give dad a break." Yukio calls from the back of the monastery, sounding exhausted, in pain, and incredibly annoyed with the hand life had dealt him, "He didn't know, and neither did you."

That's more of a punch to the gut that Yukio probably knows, since keeping dangerous demons out of his territory was part of Satan's pride and duty. To fail so spectacularly was a spit in the face. Thankfully, the piece of shit priest interrupted Satan's thoughts before he had to think too deeply on it.

"Are you two alright?"

"Yukio isn't!" Satan gestures wildly to the back with a snarl. Yukio sits still as one of the worthless lackies finishes cutting away his shirt and the small gaggle hiss at the claw marks and heavy bruising.

"I'll live."

The wound is bad by a human's standards, so Satan thought for sure that that would serve as a perfect distraction. He starts towards his room where he's stashed his weapons, but Shiro catches him roughly by the arm and pulls him back. The king of demons growls, but the Paladin is unshaken by the typical behavior.

Rin is so much like a cat, Shiro muses, angry and hissing to hide the anxiety buried in his heart. "Rin. Are you actually alright?"

The shitty priest has started to learn to better weigh his words, and Satan hates how suddenly effective he finds them, "Yeah, he didn't get a chance to touch me."

"I'm glad." A simple smile because Satan is safe, and the demon wants to both embrace it and _rip it to shreds_ so this feeling stops, "Now, let's get you cleaned up, and then we can figure out how to handle this problem."

Satan lets out a short laugh, "We don't have time for that. I say we have an hour tops before he shows up. Less if he doesn't feel like waiting until dark, and I'd bet on that since I pissed him off."

Shiro draws on all the strength being an Exorcist, a priest, and a father has given him for what he's about to ask, "What did you do?"

"I threw about thirty pounds worth of textbooks at his head and then pepper sprayed him in the face."

Yukio snorts in the back and someone drops something in shock.

"…Why do you do these things, Rin?"

"Because it was surprisingly effective. And fucking hilarious. I would've stayed to laugh if I wasn't pretty sure he was about to gore me. Once he stopped swearing and could see again, of course. But that also means he has this address, so I may or may not end up gored anyway." Satan rambles blandly as he walks off, though he isn't worried about getting seriously hurt. Not against someone as head-strong as Astaroth, who he could run circles around.

"Where are you going?"

"I need some more knives. I lost one when I crippled the ghoul Astaroth sent after us."

"You're surprisingly calm about all this."

"As far as I care, this is just another asshole looking for a fight." Satan shouts down the stairs, taking them two at a time because he feels naked without at least five weapons on him, "Plus, I seem valuable to him, being a prince and all. So, I have that to my advantage."

Yukio sighs at Rin's antics, wincing at the disinfectant is liberally applied. But he won't complain, not when he was wounded by the King of Rot- who knows what diseases the demon carried. But there was something bothering him… "I assumed that us two being half breeds would make us outcasts among Gehenna, but apparently not."

"They're more desperate than I thought." Shiro agrees, and he wonders just how many things he'll be forced to change now to keep the twins safe. They're strong, Rin especially, so he's sure they'll survive, but surviving isn't living.

Rin reappears, openly armed with knives kept on a modified belt, and Shiro suddenly realizes just where the boy's allowance keeps going. Rin looks like he's perfectly ready to argue anyone who says something under the figurative table, but now isn't the time to be questioning the boy's ability to find pointy objects.

But seeing Rin armed to the teeth with weapons like a soldier causes foul emotions to swell in Shiro's heart and clog his throat, "I probably should have trained you two harder, better, for this since I knew it would happen one day, but I hoped you two wouldn't have to become soldiers until at least a little later in life."

"Dad?"

"Satan is missing." Shiro says, and he sees Yukio and Rin both freeze at the news, "He has been, ever since the day you two were born. And, like it or not, he was what kept Gehenna stable. It's taken thirteen years, but apparently Gehenna has a chance to devolve into complete civil war soon if one of his children doesn't take over."

Understanding flashes in Yukio's eyes, "But I'm assuming his other children wouldn't take too kindly to any of their siblings trying to take over, would they?"

"Exactly, so it's likely Gehenna will split along whatever territory each Demon King claims, then start waring among itself. It'll be bad for any King who isn't overwhelmingly strong, and weak demons will probably flee to our world to escape the chaos. Unless, of course, a proper heir appears. Satan wielded blue flames that could burn anything, including the very souls of demons, and yet not one of his many children has been able to inherit that power. If any were to come forth with that power, they'd almost surely take over without much fuss. Well, less fighting than an actual civil war would cause."

"Are you implying that, Rin and I…?"

Shiro shook his head with a sigh and looks over to the younger twin, "No. Just Rin. You were weak in the womb, so the power rejected you. I knew eventually you two would have to fight, and would probably spend your entire lives fighting just to keep the demons away, so I just wanted…"

That sentiment is soft and weak, and so Satan scoffs at those feelings. It would have been better to train them from as soon as they could walk in preparation for the brutal truth of the world. But instead the Paladin had coddled them, leaving Satan free to train Yukio on his own until very recently, and now the man dared to have regrets? Ha!

But Satan remembered that Yukio grew up happy, and found it just a bit harder to spit on the Exorcist's contradictory feelings.

"It makes sense, as Rin is the reason we're in the situation in the first place, hunting down demons often enough that a Demon King noticed and all."

"Hunting?"

"Damn it all, Yukio-!" Satan spits, angry and embarrassed and betrayed.

"Apparently Rin can kill demons." Yukio continues, talking over his brother's enraged swearing and promises of serious harm if he didn't "shut your shitty mouth". Rin talked big, but he would never actually hurt his twin, and Yukio shamelessly used that to his advantage, "For good, which is hard to do from what Astaroth said. But Satan's flames can do it easily, right?"

"You snitching bastard! I thought you cared about me!"

"I do, which is why I can't just let you off the hook!" Yukio shouts back, with a viciousness Satan had honestly thought his youngest son didn't have. It's enough to keep the demon silent long enough that Yukio can break into a full tirade, "You've been hunting demons, demons Rin! There's aren't some schoolground bullies who will run once you hit them once or twice, these are actual demons! They'll try and kill you, and you've been going after them, alone, and apparently using a power you know nothing about to do it!"

Satan knew his flames better than he knew his own body, but he couldn't exactly go around saying that, so, instead, "I was just trying to keep them away from you!"

"Rin, you could have been killed!"

"I would not have been!"

"When are you going to grow up and realize that you aren't invincible?"

"When I don't-"

"You can kill demons?"

Shiro's growing look of horror makes Satan's stomach churn in some unidentifiable way that makes him want to rip the organ out just to have it stop, and- "Are we really going to do this now? Astaroth could be here any…"

"Rin," Shiro grabs his shoulder, gentle but firm, to prevent the boy from turning his back on his problems once more, "How are you killing demons?"

The stare is uncomfortable and the feeling in his guts only grows until it explodes out of him and he rips away from the shitty priest and his serious eyes. "Fucking… Fine! Fine, but only because we do _not_ have time for this."

Rin lets his own hand ignite into azure fire.

There's gasping and cursing, and Shiro sucks a harsh breath between his teeth.

"Rin…?" Yukio breaks the silence, eyeing the pretty blue flames with obvious fascination that Satan is glad everyone else is too distracted to notice. Because not fearing the flames of hell is something only a fool or abomination would do in the eyes of the Church.

"Why didn't I tell you? I'm already the son of Satan, so I assumed the literal hellfire was a _bad_ thing and I didn't want to get exorcised or something." Satan shifts with very real nervousness, since this was a delicate situation. He needed an advantage, something, anything so they wouldn't look at his story too hard. "Since that's supposedly your job, so... I thought that you only kept Yukio and I because we were still mostly human, so the fire would be…well…"

He's embraced before he's even finished a fraction of the half-baked sob-story he's cooked up on the fly and that stops him cold. Cold, yes, because he's suddenly aware of the coldness in his heart without his fire he's grown to ignore when surrounded by warmth like this. The arms around him send such contradictory feelings shooting up his spine, Satan couldn't have reacted even if he knew what to do. Warm and nice, caging and disgusting, comfortable and choking, warring feelings threaten to tear him apart from the inside.

"Oh, Rin. It's fine, it's going to be ok."

Cheap and easy pity was always a good thing. It secured his position, made them less likely to prod and ask questions, and it was always fun to take ignorant fools for a little ride through an elaborate web of lies he had crated and honed himself.

So just why did Satan no longer feel that satisfaction as he watched the shitty priest before him swallow his lies whole?

He is spared from thinking about the warm flutter in his heart that feels a bit too much like the strength Yukio gives him by a large crash outside.

The Paladin's grip is suddenly nothing but a nuisance, so Satan breaks free and rushes to the door. He can feel the weak barrier that protects the monastery waver like a mirage under a second assault of…something. Pushing through the front door, Satan instantly sees ghouls- dogs, cats, birds, rodents, it's like a small zoo -scrabbling and drooling against the barrier. It burns their rotting flesh and chips their claws, but they have orders from their master that will surely be there soon. And the barrier that protects and blesses the monastery is weak, slowly decayed from the inside out by Satan's very existence. He hadn't paid it much attention, but now the demon is acutely aware of the holes that the humans probably hadn't even noticed. Tiny, insignificant scratches, but enough purchase for something powerful to grab onto and rip apart.

"There's a lot of them..." Satan mutters, wondering just how he'll have to handle this when they break through. He's not afraid of even the largest dogs and his blood was fire and wouldn't let any of the lowly diseases take hold. But Yukio is human and one bite by the wrong demon and it could be over. So he should-

Shiro grabs Satan's arm and drags in away from the edge, "Rin get back inside!"

"Hey, wait a second-!" But he's thrown inside the doors where Yukio tugs weakly to stop him and let the other Exorcists rush about. It doesn't matter anyway, because the shitty priest waltzes back inside, ignoring the two boys in favor of shouting instructions with a clear determined authority Satan's never heard from him before.

"We're behind on preparations: pour the most concentrated Holy Water we have down every sink and drain, and then directly into the sewers! That barrier feels weak, triple it, now! I want stocks of whatever ammunition we have, summon any familiars you have under your command! Astaroth will surely be here soon."

Satan's eyebrows disappear into his hairline when Paladin reaches the gaudy central podium and casually pulls a shotgun from a hidden compartment. There's several more goodies hidden inside Satan isn't interested in since he hates guns, so it's a surprise when the priest walks over, shotgun in one hand, a box in the other. Yukio hesitantly takes it after a nod from the man, opens it, and his eyes blow wide at the sight of a clean black gun and several magazines lying in protective foam.

"Dad?"

"This was going to be your next birthday present since you've finally passed basic gun training. I understand that you're injured, but it's better to have something to defend yourself with if anything happens. And Rin, I need you to follow me-"

There's a crack beyond human understanding, and suddenly Satan feels the pressure on his shoulders he's come to associate with safety be blown away. Foul air rushes in, carrying the scent of rot.

Astaroth is here.

Satan plasters a trademark grin he hasn't used in years on his face and boldly struts out the door while the humans are gagging on the sudden smell. He's missing his usual fangs and eyes and hellfire, but if the way Astaroth loses his cocky smirk when they meet eyes is any indication, it's still just as terrifying. Maybe even more so to see such a familiar look after over a decade without.

"Hi there. Came for a family visit, hmm?" Satan says with cheer as fake as his human skin, indulging in his more dramatic tendencies. If anyone askes later, he'll cite that he was buying time, since he doubted "I wanted to fuck with him for running my day" would be an acceptable answer. "But you should have given me some warning, Astaroth! I could have prepared some food, cleaned the house, offered you a glass of Holy Water, taken your things…" he eyed the backpack the demon is holding in a tight grip.

"But until then, I want you to get the fuck out of my territory." Satan finishes plainly.

Astaroth laughs at what must seem so much like a kitten baring its claws. "Such a strong spirit, young prince! But it's no good that you've gotten attached to this lowly land when you should be home you know! No, no good at all."

Satan ignores the implied threat, "We're family, so I'll let you off light if you leave now." Family, love, the things that Satan had sought so desperately he had instead driven them away. It was in his grasp now and he wanted to hold tightly and never let go, but he also wanted to be more selfish and have more things to hold. Yuri would have wanted to mend his tatter life, so he owed it to her to at least try, "Come back later without your pets and maybe we can talk things out a bit?"

"Talk?" Astaroth starts slowly, letting the word droll out of his mouth like something so disgusting he can't even process it, "You want to talk and spit whatever lies these Exorcists have been feeding you?"

"Because I'm going to trust whatever shit some flea-infested glorified rat that hasn't been a threat since the dark ages tells-"

Astaroth flings the backpack at Satan's with lethal force, something he easily ducks. He hears many things (everything) inside it break to pieces when it hits next to the door to the monastery and nearly takes a peaking Exorcist's head off.

"You missed, asshole!" Satan jeers, ignoring the fact that he gets stared at like he's nuts. But he can't help it, his blood is rushing at the idea of his first real fight in years. Oh he's hopelessly outclassed in raw power and killing capabilities, but Satan is fast and crafty and knows all of Astaroth's patterns and weaknesses. He overextends, he relies too much on brute force, and he's bad at seeing the bigger picture.

This would be easy.

They both go low and start circling each other like the apex predators they are, Satan with glinting knives and Astaroth with dark claws. With the way Astaroth is trying to corral him closer to the gate, the plan is painfully clear: pin Satan between the surprisingly quiet pests the demon had hoped he had forgotten about and then swarm him. But a surprise is only effective if it's unknown, and Satan readies himself to sprint and slide his knives between those ribs-

A thunderous crack and Astaroth went flying from a gunshot.

Shiro sprints out, shotgun in hand and looking pissed, a whole gaggle of Exorcists behind him spilling out to attack the ghoul swarm, "Rin, what part of stay inside do you not understand?!"

The ghouls scatter and attack viciously, and Satan curses as he stabs and slashes at a poucing cat, all while trying to crush a dozen rats trying to bite through his shoes. "Actually you old told me to get inside, you said nothing about staying there!"

The Paladin chucked a Holy Water grenade into a pack of ghouls, their dying screams not enough to fully mask his frustrated sigh, "Go protect your brother."

"Which one? The one you just shot?" Who had bulked up to eight feet of pure rage and was currently ripping some poor Exorcist's familiar to pieces, "Or the one you just left alone with a gun?"

"Go inside already!"

"I'll do whatever-!"

Another crack of thunder and the ghoul that had been sneaking up on them turned to dust. Slowly, the two looked over to the doors of the monastery and state at the sight of Yukio leaned against the doorframe, gun glinting in the light. And did he ever look mad.

"Would you two stop fighting already and focus!?"

"R-Right!"

Satan takes a moment to drink in the situation and actually think of a plan instead of blindly throwing himself at the enemy like the fodder had done. Astaroth had just finished goring a scarecrow familiar and was using part of it to bat some poor Exorcist across the lawn. Ghouls kept encroaching and growing even as the Exorcists destroyed them with fists and fire and water, ignoring the seals that should have kept them away in order to assist their king.

Satan knew a lost battle when he saw it, and it was only a matter of minutes before they were overrun. So he would just have to cut off the head. "Hey, old man, how good are you at negotiations?"

"This situation is beyond negotiation, Rin!" A whole book's worth of fatal verses spill from the Paladin's lips and a line of demons goes up in smoke.

"Sorry, I meant threats." Satan grunts, losing his knife to pin a crow covered in boils to the wall of the monastery, "Eh whatever, just stand there with your shot gun and look menacing when the time comes, ok?"

"Whatever you're planning to do, don't."

"Hmm…No."

"Rin!"

Satan takes off at an inhuman dash, drawing just a bit on his power to leap over ghouls with long strides. He slashes apart a decayed fox that's hassling one of the useless fodder Exorcists with easy, scattering the pieces to prevent it from ever getting back up. The man, who Satan had seen punching demons with little more than his fists and some blessings, tries to thank him, but Satan ignores him and grabs the container of Holy Water he had dropped. It's half empty and unwieldy large for a speed fighter like Satan, but the lost weight is enough to make it manageable.

He takes off at a sprint to the fire-breathing Exorcist, who was desperately trying to hold of Astaroth to little avail, "Hey, fatty! Boost me!"

He ignores the indignant cries of "My name is Maruta!" from the fat man and rushes him. If the idiot doesn't get the message, he'll just use his face as a springboard instead. But no, the man finally processes Satan's shout and scrambles to get into position to boost the demon's jump high into the air, over even Astaroth's towering form with the power.

A perfect height to upend the entire container of Holy Water on the demon's face.

Astaroth roars and lashes out blindly, but Satan lets the plastic container shield him from slashing claws. Falling, he plants his feet square in the demon's face and shatters that stubby nose to pieces and jumps straight up with an elegant flip from the toppling titan. The pain and weight is enough to send Astaroth falling to the ground like a great beast toppled by a mouse, and to add insult to injury, Satan uses his downed form as a crash-pad, driving a his heels into a soft stomach. Astaroth tries to move, is a heartbeat away from ripping Satan's mortal shell to pieces, but the elder demon is ruthless and grabs the thick tail that is lashing angrily about and lets his flames just barely kiss it. It's not enough to burn, but it's uncomfortable warm, and beneath him Satan can feel the great body of Astaroth lock up with fear.

Finally.

"Now, you're going to calm the fuck down, and you're also going to listen to me, ok?" Satan isn't mad that Astaroth decided to throw a hissy fix, his kids did it all the time, but he is still rather pissed that the demon had threatened Yukio. Normally he wouldn't give a damn how many times his kids destroyed each other over petty things so long as no one actually dies, but Yukio is still fragile and mortal and would die if his body was destroyed.

"Y-Yes, young prince…" Astaroth chokes on his words and Satan barely gives Shiro a glance when the Paladin appears by his side to point his shotgun at the demon's face. Well at least the man was on board with the plan, even if he hated it.

"Good. See, we can talk things out. Now, you're going to leave this place and you aren't going to ever come back, or else I'm taking your tail as a trophy. We might be family, but don't think I won't burn a shitty brat like you until you learn to listen to me." A warning flicker of flames against skin gets a frantic nod, "Oh, and you're going to say sorry to Yukio for hurting him. That's not what big brothers are supposed to do, got it?"

Forgiveness was important, as Yuri would say.

"Forgive me, please forgive me!"

Yukio looks immensely confused, and, not knowing what else to say, mumbles "Ok…?"

"Good. Oh and don't tell anyone else that we're here, ok? You lost so you have to listen to me, that's how it goes. Don't even send over someone you don't like because you want me to kick their ass, go do that yourself you lazy bum." Astaroth is _looking_ at Satan with open admiration, even if his distorted face makes it hard to identify, "What?"

"Nothing. You just truly are so much like our fathe-"

Shiro shoots his shotgun and misses Astaroth's head by millimeters. "Be silent with your lies, demon!" And then he starts to rapid-chant Astaroth's fatal verse.

Astaroth doesn't even fight, "Please come to Gehenna before it collapses, my prince."

"I'll do whatever the hell I want." But there's no bite to the reply, it's just a simple fact in Satan's mind.

Astaroth smiles, and is driven from the human's body in a burst of black and bile. The demon's soul flees, and Satan feels even the tail in his grasp disappear into the ether and he lets his hand go slack, fire once again curling deep into his body and behind a crumbling seal. There's no real fuss – the ghouls that had gone silent flee – and less fight than Satan had thought there would be from one of his kids. He knows this isn't over, but also knows that Astaroth won't share what happened here, if only for his own pride.

Satan stands up, dusts off his knees, and lazily stretches. Everyone is staring at him, a child who took down a Demon King without a scratch, a child with flames of hell, and he can't care what they think about what they just heard. Instead, he flashes them a grin that's all teeth, "Well, that went well I think!"

Shiro smacks him upside the head.


	23. Hold in These Hands

Chapter 22: Hold in These Hands

 **I've been reading the manga a lot recently in an attempt to try and peace together some sort of long-term plot before I progress much more. Considering how in the manga there's a lot of other parties that act in direct relation to Satan himself, it would be a bit stupid of me to have them all act the same considering how Satan has been MIA since the Blue Night.**

 **Yes, I do know that there are some MASSIVE contradictions in cannon later on (Section 13 gives me a migraine to just think about it…), but most of those will basically be ignored since it's already too late, and they'd ruin the story anyway. This was also originally going to be combined with the next chapter, but I needed to re-write it pretty much in its entirety, so I decided to post just this.**

* * *

It is 2 a.m. and Satan is nursing a cup of hot cocoa, watching the Exorcists try and clean up what they can after Astaroth's little hissy fit when Shiro walks up to him and sets a sword that feels like hellfire in front of him, and Satan decides he's way too tired for this shit. They'd been stuck dealing with the police for hours, and then he'd been roped into doing major clean-up for several hours. That wasn't even counting the lecture the shitty priest had given him up until the minute said police had arrived, spewing things about "safety" and "common-sense" and "suicidal, reckless behavior". Now Satan just wanted to sleep because the barriers were back up (weak, but they would suffice) and he knew he would need all the strength he could find for the coming days/weeks/years/eternity.

"Fuck off until the morning, I wanna sleep." Satan muttered into his cup of blissful sweetness without even really listening. He really shouldn't be this tired, but cut off from his flames as he is, he loses his energy annoyingly fast, and the day has been emotionally draining.

Yukio just sighs into his cup of water, which he'd chosen over something, well, _better,_ because apparently he didn't want to be up all night. Satan cut his eyes over to the clock and peered over at the time- 2:13 a.m. -and sighs. So much for that plan.

"No Rin, this is important." Shiro insisted, ignoring the way the boy rolls his eyes, but is too tired to give a real fight.

Satan proceeded to only half-listen to the shitty priest's rambling about the sword that holds the bulk of his powers. He stared with bleary eyes as the man went on and on about how important it is, about how the seal is weakening, and about becoming a 'true' demon if he draws it. He stared at the sword and the seal that's worn down to almost nothing, and knows he could easily pull his powers free from the blade any second, can feel it hum and sing to him like a lost friend, the power dancing with his own and caressing his soul.

It's annoying when he's trying to learn how to sleep with his eyes open.

And when the man starts talking about plans to leave, to uproot the life Satan has only just gotten comfortable with, over some delusional fear he has, Satan downed the rest of his drink and slammed it on the table to interrupt the shitty priest.

"No."

Shiro sputtered, "Rin-"

"I'm not leaving." Yukio was happy, and Yukio had a future he wanted to aim for. Yukio wanted to be a doctor, and whether that be for the mundane or supernatural, it didn't matter: all that did was that his son received a high-quality education to do whatever would make him happy. And so, "This room, this building, this entire damn town, is _mine_ , ok? It's where Yukio is going to grow up and be happy, and if anyone comes after it, I'll destroy them."

"Rin, I'm sorry, but we can't do that. Now that Astaroth knows where you are, he'll-"

"He won't do a damn thing." The demon interrupted, wearing well-worn authority that forces the human to freeze, "I fought him, I won, and so he'll listen to me and fuck right off. And if you and your little 'posse' would actually do your jobs, then there won't _be_ another incident. Or one in the first place."

There's going to be another fight, Satan can just tell by the way the shitty priest's eyes alight with that fickle inner strength he has. They may have agreed to live together in peace, but that hardly means they get along that well, and Satan will tear the man down the moment the need arises. He's done it plenty of times in the past, so he'll do it again. Very little, if anything, has changed between them.

But Yukio, ever-growing, has changed very much, and sees the argument with only a sigh, "Dad, Rin and I will be old enough to enter high school in a little less than two years. I know I said I hadn't decided on anything for certain yet, but isn't True Cross Academy one of the most heavily protected places in the country?"

That stops the two of them short, Satan with interest, and Shiro with slight surprise. The moment the words left Yukio's mouth, Satan knows exactly where to guide the conversation and how it'll all end. It must be strange for the human, Satan thinks, to see a child learn to manipulate so naturally. But Satan has known Yukio is very clever for some time now, more so than he (Satan just has eons of practice), and likely nearly as clever as his eldest siblings.

Shiro isn't an idiot, however, and pieces together what Yukio wants well enough and grimaces as he is led into a corner, "I know where you're going, but I doubt Rin could get in with his grades."

"Oi!"

"Relax, Rin." Shiro says and offers a truce in the form of a new mug of hot cocoa. Satan takes the nearly scalding mug with a grumble, but he'll keep his peace. For the moment.

Yukio accepted his own mug, finally giving into temptation, "True Cross Academy has some of the highest standards in the country, to the point that even I barely make the cut in some places. But besides that, Rin could probably get in on a multilingual scholarship, assuming True Cross has one."

"I could?"

Yukio looked over to his clueless brother with just the tiniest bit of envy that he found such things so easy that he never even considered it impressive, "How many languages do you know again? Three?"

"Four." Honestly it was probably close to forty, but a good number of those were considered dead languages, and even more were too obscure to explain how or why he had learned them.

"See?" Yukio sighed with a wave, "The headmaster has to be an Exorcist, so I'm sure he or she could pull some strings. And I can help Rin get his grades up."

"That's still two years." Shiro reiterated.

Satan rolled his eyes, "Then do your job."

"Ouch, you really aren't letting that one go, are you?"

"It hasn't even been twenty-four hours yet!"

Satan snarled at the shitty priest's chuckle at that, almost overwhelmed with the familiar urge to sock the man in the face. How dare he laugh at the king of all demons like that! He would gouge those eyes out with his own broke glasses and then-

A hand ruffled Satan's hair and all thoughts fled his head except one:

"I'm not a damn cat!"

Shiro laughs and Rin ducked away from the contact, scrambling out of his chair and backing away with a venomous glare. The image was ruined with how he still clutched the cup of hot cocoa protectively to his chest, which he sipped after a moment. Angrily.

Shiro is not a very good man, he has made many mistakes in his life and has flexible morals at the best of times. But he doesn't want to see Rin devolve into a rabid dog, doesn't want to see Yukio to become a pawn beside his brother, but the two cling to each other. Rin even more so is vicious with how much he values the mundane, and without it…

"You really don't want to leave here, do you?"

…Rin would surely become something frightening when he entered Shiro's world.

Satan, realizing he was bunched up and unreasonably tense (like a _cat_ , damn it all), straightened with a sip of his drink to cover the movement, "It's better to dig your heels in and refuse to look weak when you've got the advantage." To retreat was a weakness that demons just couldn't resist pouncing on, "And yes, we do have the advantage: I kicked Astaroth's sorry ass, which means that even if he blabs we'll still look strong enough no one will decide to attack us without some planning. And I seriously doubt he will, since what demon wants to admit that they got beaten up by a thirteen-year-old human? No, if Astaroth tries anything, it'll be by himself, and we already know how to prepare against him."

There were problems with that logic, just as there were problems with Yukio's proposed plan. Both of them were still young, Rin thought himself invincible and able to handle any threat that came his way, while Yukio believed Shiro to be near-perfect and able to protect them both forever. But-

"You two have really thought about this, haven't you?"

"Yes…"

"It's just common sense!"

Shiro sighed at the twin responses, and, knowing full well he was going to regret no matter what, so he might as well be just as selfish as he was on that day, in the cold and breathing the ash of the damned. "I make no promises, but we'll spend the next few days checking the town for any activity and setting up extra defenses. You and Yukio will have to stay inside and can't go anywhere without at least one of us accompanying you, but if we deem this town safe, then we'll see. However! If things ever change, or if I ever even think there might be a serious threat to you two, then we're leaving. We're also going to starting your training- your real training."

He didn't want to make Rin even more vicious, but hopefully, by some miracle, preserving a mundane homelife would balance him.

Satan eyed the human suspiciously but decided to take things at face-value until he got enough sleep and felt less horrible, "Then we're through here! Goodnight and good riddance!"

He nodded, stood, and waltzed back to his and Yukio's room. He would have to check every corner for his own peace of mind, and he needed to do that soon if he was going to be thorough.

Yukio, ignorant to all of this, only noticed that Rin had decided to be rude and leave his empty mug behind, "Rin, put up your cup!"

"Can't hear you, already half-asleep!"

"Rin!"

"Yukio~!"

The younger twin made to storm up the stairs, but stopped at the firm pressure on his uninjured shoulder. Shiro just shook his head with an exasperated smile, "Let him go, your brother is tired."

There were so many bags and lines on Shiro's face, Yukio realized suddenly. Shiro looked so tired, with something much deeper and heavier than just missing a night or two of sleep, and it haunted his very bones, wearing down his spirit until he had no choice but to smile or buckle under the pressure. His eyes were so very old, but filled with the desire to keep going.

Rin's eyes were the same sometimes, but a thousand times older and wearier. Just how long had his brother been hunting demons in some misguided attempt to protect him?

"Dad, what's actually going to happen now?"

"I don't want to force your brother to do anything, because that's when things can get…unpleasant with him." Rage might spark a fire that would leave a lot of people dead and Rin's head on a chopping block, "But to think he's been tapping into that cursed fire for who knows how long…Well, things have just gotten a lot more complicated."

"They usually do with Rin. Sometimes he just looks so…" Old, ancient, worn-out and crumbling with only a flicker of life remaining, blazing only when he say Yukio, as if Yukio was his entire universe, "So _tired_ , and I wonder just how much he's been doing behind my- _our_ backs in some misguided attempt to protect me…"

"Long enough to know how demons tend to fight and the reflexes to take down something stronger than himself." There had been no fear when Rin had attacked Astaroth, no regard for his own safety when one good hit would have torn the boy in two, and the confidence hadn't been misplaced either. Rin could read demons and knew their main weakness, their tails, without having ever been told, "I have a few things I think I can at least try to do, but all of that depends on what the demons do next. So, I need you to keep an eye on your brother and keep him out of trouble."

Yukio nodded, looking to the neglected sword on the table and can recognize that several dizzyingly high-level seals have been applied recently and rather crudely to the sword as a sort of stop-gap measure. There's no way that his father will be sleeping anytime soon with the refinement that's clearly needed if Rin wants to keep drawing on the flames without rotting away that vessel completely. They're both pushing themselves so very hard, so Yukio should just…

"I can only promise to try."

"That's all any of us can do when it come to Rin. Now go on, get to bed."


	24. Tighter, Until You Bleed

Chapter 23: Tighter, Until You Bleed

 **I swear, there's only like 1-2 chapters before True Cross, during which the fic will become more like an actual story.**

* * *

Three days later, and Satan could feel himself going stir-crazy with being locked up in the monastery. He and Yukio had supposedly come down with a case of the flue as far as the school was concerned, but even the homework and lessons they got delivered to their door could only keep him so busy for so long. Yukio's shoulder was healing with no complications thankfully, even if it would almost surely scar nastily. Satan hated sitting around and itched with the urge to patrol his territory after such a breach, but simply can't because he has to be, bah, _diplomatic_ if he wanted to stay. So instead he idly takes pictures with the camera that had somehow managed to survive that crazy night and sharpens his knives while looking out the window with careful eyes. He and Yukio had had a few fights over what he was and wasn't allowed to do anymore, and Satan will play along for as long as the prying eyes are staring a bit too intently at him. But he needs to patrol and protect eventually.

It's been three days and Satan is incredibly bored, yes, but he quickly decides that he really shouldn't tempt fate when the doorbell rings.

He's the one to open the door simply because he's the closest and comes face-to-face with Samael, who looks at least 30% more ridiculous than Satan remembered. Still in a gaudy amount of white and purple, with stupid looking puffy-shorts and striped _tights,_ and a damn cape of all things, and that fucking hat-.

"Well good afternoon! My name is-"

Satan slams the door in Samael's face. Or tried too, but the idiot had stuck his foot out to catch it just in time and laughed like this was a funny game. So Satan laughs right back and stomps on said foot and makes sure to lock the door. Not that it'll stop that lunatic, but hopefully the idea of being a gentleman will restrain him. Shiro walked around the corner just in time to catch the tail end of the exchange, and gave the boy a _look_.

"Hey old man, there's some weird jester-faggot outside with a cape!" Satan shouts loud enough he knows for a fact that Samael can hear him.

Shiro twitched, "Rin, don't say things like that! Wait, 'jester'?"

"Yup. You should get your shotgun, he tried to force his way in and everything." Satan continued, stepping back to let the shitty priest past. Despite everything, Samael is smiling perfectly serenely when Shiro opens the door, as if he hadn't been assaulted and insulted.

"Ah, it's been too long, Shiro! I see your son is full of _even more_ _energy_ than your descriptions would have led me to believe!"

Ah, no wait, Samael was clearly angry, but just had the tact to not do anything, thinking the 'foolish child' was just baring his fangs. He _did_ put up with Amaimon more than anyone else could, who Satan was pretty sure was a bit touched in the head and/or socially retarded. Well, even more socially retarded than any of his other kids. Well then…

Even Shiro could feel the annoyance permeating the room and sighed. There went any chance of a good first impression, "It's good to see you too, Mephisto. And please excuse Rin's behavior, he has…quite the mouth on him I just can't seem to curb."

"Of course you would know a guy like this..."

May God be merciful, Shiro prayed, "And just what does that mean?"

"Oh nothing, nothing." Satan said far too innocently, waving the question away. But he stopped and let his eyes drag over Samael's form (he could call himself whatever he wanted, but Samael was the name his mother gave him, and so he would forever be Samael) with heavy purpose before looking at the shitty priest with an evaluating nod, "This is one of those 'progressive churches', so I'll be good and just wish you two well in life!"

The implications take a full two seconds to hit Shiro, which is plenty of time for Satan to make his tactical retreat.

"Rin!"

Satan retreated with a cackle, flashing the hardly-phased Samael a peace sign just so he could see one of his brows disappear into his hairline in curiosity. It probably wasn't a good idea to make himself interesting to someone with absolutely no boundaries or morals like Samael, but screw it all, Astaroth was already involved and if things hadn't drastically changed over the past decade, then Amaimon would get wrapped up in this mess sooner or later, always chasing Samael's coat tails because no one else wanted to deal with him. He didn't even know what the other half of his kids were up to, or if they were involved in Lucifer's little club or not. No matter what he did things would get out of control, so he was fine as long as he didn't sprout wings and announce who he was. Well, it would get difficult for the 'adults', most of who felt morally obligated to deal with the problems themselves. Which, good on them, he would cheer them on as they solved his messes as he napped and taught Yukio how to slip a knife (and, one day, claws) cleanly between ribs.

Mephisto watched the impossible child flee up the steps with a cackle that was a bit too familiar for comfort and wondered. The malice that Shiro had once liked to report and complain about was nowhere to be seen, even though he had been sure it would destroy the 'happy family' facade the Paladin was desperate to maintain with every Gehenna report he received. "Well, he's certainly lively! And how are you doing on this fine day, Mr. Fujimoto?"

"He's a brat with a mouth that's gotten him in trouble more times than I or the school office can count, and you can't even begin to imagine just how much he worries me." And yet the man somehow sounded so fond of the literal hell spawn. Honestly, Mephisto would never truly understand these contradicting creatures, as much as he was fond of their creativity and spirit, "He sassed Astaroth. Sassed a Demon King with a small army of ghouls behind him as if it was just some playground spat. And I'm managing. Somehow."

"Well, Astaroth did intrude." And was successfully repelled, not by the Paladin (directly), but a tiny demon who shouldn't have had a chance even when blessed with father's illusive flames. Interesting, but old news.

"Yes, I know. But that's not why I called you here to talk."

Maybe it was foolish to rely on a demon to tell him truths that no one else would, but Shiro had long realized that the deeper he treaded into a web of lies and conspiracy, the only people he could trust were those who wore their intentions one their sleeves.

"Ah yes. There have been some interesting developments lately. Lucifer has officially refused to claim the throne, leaving it open to any who wish to take it." Mephisto began, and maybe he was just a touch disappointed when Shiro didn't ask the obvious question. He really was becoming predictable, "I myself cannot take the throne without abandoning Assiah, and I can't do something like that when my dear brother is clearly planning something. Lucifer does nothing in halves, so this behavior is worrying even me, I'm sure you understand. Therefore, Iblis has mounted an assault against those who believe that only those of the blue flame should rule."

"Iblis is the one who wants to lead war against Assiah, right? So where does that leave us?"

"With my aid and favors, it'll take some time for him to win, but he _will_ win, make no mistake there. Without a proper heir, the blue flame faction will slowly lose support and crumble from within. I imagine that's why dear Astaroth paid you a visit. Don't worry, I've taken care of him, though I doubt he would have made another attempt even without me." And wasn't that something, already successfully cowed by and practically worshiping the youngest prince, calling him the second coming of Satan.

As if- the boy was far calmer than Satan had been for the past several hundred years or so, what with his declining sanity.

"How long do we have?"

"A year, at most, before Iblis takes the throne." Mephisto admitted, and he could feel Shiro doing the mental calculations and preparations, "However, he won't be ready to properly assault Assiah for another decade, maybe five years if he rushes things. But plenty of his brothers are against him or at least neutral to him, so he'll have very support there, and they hold most of Gehenna's power between them."

Still, "This entire situation is terrible."

"Yes, yes, it is all very dire and dramatic, making it the perfect stage for an unprecedented move to occur, no?"

* * *

It took only a few more painfully boring days after Samael's visit for Satan and Yukio's house-arrest to be lifted. Honestly, it was overkill, considering how Samael had reassured them all that any possible issues with Astaroth had been taken care of, and even going so far as to lay some rather powerful seals around the monastery. Sure, the demon had openly admitted to wanting to use "Rin" as a puppet ruler to keep the balance between Assiah and Gehenna once he had grown some more, but that wasn't anything Satan hadn't considered once his warward son had shown up (who was in charge of a school, what the _fuck_. He knew about the Exorcist thing, but a _school?!_ Yukio's future school!?). It was hilariously ironic, but to anyone who wasn't "in the know" it made perfect sense: "Rin" had strong ties to Assiah, so having him on the throne of Gehenna had to be better than any of the others.

" _Yes, become more vicious, become more powerful, and become the strongest!"_

Samael really had too much of a taste for the dramatic. While Yukio had gotten angry over the thought of anyone using his 'big brother', Satan had barely prevented himself from laughing himself sick over how neatly everything had decided to fall into his lap. He was allowed to stay in his city, he had an easy in to True Cross and could stay by Yukio, and he was going to be plopped back on his own throne with others doing most of the fighting for him.

He wished he had planned this, he really did wish he was that good. But sometimes fate was fickle like that, and Samael liked to think himself so clever and above everyone else.

Even Samael getting petty revenge for the equally petty door incident by disguising an attempt to scalp him as a 'friendly' hair-ruffle couldn't damped Satan's mood. Ok, maybe it could because that had both hurt and been insulting, especially when he could _see_ some of his hair on the bastard's gloves, but whatever, that didn't mean much in the end. Not in the face of a simple fact.

Satan had a familiar now.

He would give the crappy priest credit for one thing at least: he had good taste in demonic guards. Cat Sídhes were fairly powerful while still being discrete and agile enough to get around almost anywhere without being noticed. They also tended to be fiercely loyal and, if the split tail was any indication, this one had survived for some time. So it wasn't some random straggler.

It, well he, was also 'gifted' with the ridiculously uncreative name of "Kuro".

Satan rolled his eyes when he realized that the black cat was named exactly that: black.

"Of course you named him that."

Shiro ignored him in favor of handing the currently small bundle of fur to Yukio, who clearly didn't know what to do or how to hold a cat. Satan may or may not have taken a picture instead of helping, and Shiro gave him a look that clearly said he was going to want to see any copies that got printed.

"As I was saying, it's impossible for us" Shiro gestured to his generally useless lackies, "to follow you constantly, so Kuro here will become your shared familiar. He doesn't need to be summoned and technically his contract is with me, so there's no threat to either of you."

"I didn't know you had a permanent familiar, dad." Yukio said, nearly fumbling the squirming demon that was very insistently demanding attention.

"I tamed him when he was harassing a construction site some time back, and he's been a sort of guardian for True Cross Academy for a while now. I talked to Mephisto and he was happy to give Kuro back to serve as a guard for you two."

Kuro finally had enough of being held and leapt to the floor, where he very promptly whined, _'I want food already! I was promised food if I stayed in that stupid stuffy cage!'_

"Hey, I think your cat is hungry." Satan said when the cries got on his nerves and Shiro was too busy trying to explain the specifics of the familiar contract with Yukio.

"Oh, right, could you feed him, Rin? It'll be good for him to be comfortable around you two before you go to school Monday."

He thought about telling the shitty priest to not be so lazy, but stopped, "Fine, I'll use that turkey that's going to go bad."

Satan led the demon cat into the kitchen and fed him exactly as he said he would. Once Kuro had devoured the mean, he let his hand absently stroke the demon's silky fur and began his real objective.

"Now, Kuro was it?"

 _The Cat Sídhe looked up at that, and it looked like that stupid nickname was going to stick around,_ _'Yes? Do you have any catnip wine, err…'_

"You can call me Rin. And no, I don't."

 _Ears flicked up and green eyes widened,_ _'You can understand me? Wow, not even Shiro can do that, and he's the best!'_

"I have demon blood, but that doesn't matter nearly as much as what I'm about to tell you." It wasn't like the Cat Sídhe would be telling anyone about that little tidbit so long as he was playing guard for the twins. "You may be told by that shitty priest to protect both of us equally, or even to protect me first, but I want you to protect Yukio exclusively if anything ever happens, ok?"

 _'But-'_

"But nothing! I can defend myself, and I'll do my best to protect Yukio, but he's a lot more fragile than I am." Humans in general were so breakable and often couldn't properly heal. Scars, imperfections, living itself slowly wore them down to dust, "And, one day, hopefully far into the future, something big will happen. And when that happens, Yukio might not want me to protect him, at least for a while. So that's where you come in, alright?"

 _'But why would Yukio not want you to protect him if you're strong?'_

Satan thought of how Yukio's world was destined to shatter to itty bitty pieces one day, shards of memories and jagged feelings that would cut his mind and soul to bits. He would surely bleed, surely cry, and surely hate whatever happened to Satan's human body when his demonic blood was set free. Claws and wings, scales and skin like leather, fangs and fire- a revolting sight ripping free from a human shell.

Yuri had still had the courage to love such a beast, but could a miracle ever occur twice?

Maybe it wasn't wise, but Satan would push the answer to that question as far down the line as he could.

"It's complicated."


	25. The End of the Beginning

Chapter 24: The End of the Beginning

Satan wasn't sure when it happened, but one day, thirteen years into his masquerade as a human and several months after Astaroth's little stunt, he woke up and realized that he was…ok. Emotionally, that is.

At some point, his rage and hatred and regret had started to fade. He didn't know when or how or why, but it was so slow that he didn't notice, like the way the ocean dulled and eventually dissolved the land it beat against, and his boiling emotions cooled to a simmer. He still felt rage over what had happened Yuri, but it was no longer an ever-present white noise. He still hated that Yukio called that shitty priest "dad" instead of him, but the words only irritated him instead of acting like nails being driven into his skull. And he still regretted that he hadn't held tight enough, hadn't acted earlier on what he and Yuri had found blossoming between them, but it was a dull ache that reminded him of what could be lost instead of the feeling of his heart shredding itself. It was strange, because he was a long-lived creature that kept grudges for millennia, and yet the biggest slight against him was being…not forgiven but dulled with relative ease.

He remembered how he spent his days training and playing with Yukio instead of stewing and raging, and it made a little more sense.

Would Yuri be proud of him? No, no she wouldn't. He had killed a lot of people to try and save her -something she would have never wanted- and he continued to kill selfishly to protect Yukio, even as he knew how fleeting mortal life was to his eternity. He was still loud and rash and quick to anger, and he was so terrible that he possessed the body of her dead child just to be closer to his last light. Really, he was just the worst there was, and he would never be a good person.

For some reason, Yuri had been alright with his jagged imperfection. She had wanted him to be 'better', not 'good'. She wanted him to understand and work with humans, but she didn't demand that he do anything more than try to be 'better'.

So, Satan watched.

During his years playing human, Satan had learned many things about what it meant to be a human. They glorified conflict and feats of strength and yet were terrified of being hurt so much that they punished even the hint of violence. Children got some leeway with the thought that they didn't know their own strength and drowned in their emotions, but the older he grew, the less acceptable violence was, even if he never killed them. So he just moved on to hurting people who either wouldn't or couldn't tell the authorities about him. Plenty of prideful idiots who were physically older than him wouldn't dare tell who had beaten them so bad, and criminals -murders, pedophiles, kidnappers, rapists, disgusting filth that no one would miss- weren't even given a chance to go to the police. And so the demon found peace and made the town his nest and home for as long as it would allow. Even months after Ashtaroth's appearance, things continued to go smoothly.

But sometimes Satan…forgot just how fragile humans were. Like the other day, when some teens in his and Yukio's class had finally discovered what crude humor was and started making jabs at how they must be the "altar boys" at their monastery behind their backs. It shouldn't have meant much, it should have just been the ramblings of the mindless rabble that tried to claw down someone superior to them in whatever way they could. So he had ignored them because he promised to do better to get into True Cross Academy, but he had heard that shitty priest's name thrown into that filth and had, well…

He really only remembered that the brat's nose had made a very satisfying crack.

And so he was suspended from school for the rest of the week. Yukio might have been more upset that he had broken he "good streak" but instead the boy had just smiled with exasperation and a certain fondness as he walked the other boy home.

"He was defending your honor." Yukio had said when it looked like a fight was going to break out when they arrived back home.

"Like fuckin' hell I was!"

"Language!" Shiro hissed, trying (and failing) once more to clean up Rin's behavior before he entered True Cross and ruined his reputation with any Exorcist he met. He would have threatened to get the soap if the stubborn boy hadn't laughed last time at said threat and started drinking the dish soap just to prove some idiotic and nonexistent point.

The trip to the hospital hadn't been fun for anyone and now Shiro had to worry that his idiot and half-demon son would drink Holy Water just because someone told him not to.

Yukio ignored the futile battle Shiro insisted on fighting, "I thought it was very sweet if you ignore the part where you broke his nose."

"Honestly Yukio, I thought you were smarter than that. I can't defend what was never there in the first place."

Shiro had quit smoking a while ago, but by God, he needed a stiff drink, "Hey now, when are you going to grow up and stop being such a brat?"

"Please go easy on my 'big' brother, he's very bad with his feelings but I swear, Father, he's trying. Beating up someone for you is just his way of saying he likes you."

"Like a cat bringing back dead birds. I fear what he'll start doing to show he 'likes' a girl…"

"You bastard, I'm not a cat!"

* * *

Even with Yukio's defense of him, reparations still had to be made, and so he was stuck being the glorified pack mule the next time he and Yukio were allowed to shadow Shiro and the other Exorcists as they cleaned up the borders of the city. He wasn't allowed to stab anything or participate in general, even though Kuro (that terrible name _had_ stuck), who was now technically 'Rin's' familiar got to help take down the smaller demons. Kuro, who was supposed to be a powerful demon, but instead he had been drafted to chasing out small demons from their hidey-holes and didn't even mind being given such demeaning work. No, instead the _Cat Sídhes seemed ridiculously pleased when it brought a struggling hobgoblin to Satan's feet, twin tails waving happily._

' _Rin, Rin! Look, I caught it!'_

"Fantastic, you caught a rat." Satan drawled, bored out of his mind. He wasn't allowed to even fiddle with his camera since he took pictures of "top secret Exorcist operations" if he had it on hand. What was wrong with wanting to capture Yukio's first real kill? It wasn't like the film could properly record the demons anyway.

' _Rin, did I do good?'_

"Eh. Also, don't play with your food unless it did something bad to you." Satan had absolutely no qualms with torture, but Yuri would at least want him to only do it when someone had committed a seriously slight against him.

Stuck with nothing to do, Satan could only watch and feel his anxiety rise every time a demon came within even twenty feet of Yukio, never mind that the shitty priest was acting as a human shield. If he needed, he could be by Yukio's side in under five seconds, but that was still a long time in a fight. Sure, his son was now very proficient with his gun and knew enough hand-to-hand to take down a man three times his size, but he still _worried_.

Their Exorcist training had been sporadic and spotty for the most part, with Shiro having an obvious preference for the more practical side of things and being a stern teacher. Satan refused to let the old man cut into Yukio's studies, and so a bargain had been reached: they wouldn't be given a very heavy load and would still attend the Exorcist cram school as a formality and take the Exwire exam to streamline the process and prevent accusations of favoritism. The Paladin had given in far too easily, so Satan was sure that he simply wanted to delay them being put on any sort of real combat duty for as long as possible. And while Satan entirely supported keeping Yukio out of danger for as long as possible, he also realized that Astaroth hadn't come to Assiah for shits and giggles.

Eh, he could deal with Gehenna whenever he wanted. The idea of getting direct access to the Exorcist's main base and information was too good to pass up. Even if he had no active plans to use it against them, that didn't mean things wouldn't suddenly change.

He also might have also planned to raid Yuri's files the first chance he got, assuming they hadn't tried to scrub her from history.

It was only a whisper of a sound, but Satan knew instantly that something was _above_ him.

Satan brought his free arm up to defend himself and hissed as the…creature sunk its long fangs into his flesh. Spindly, too-long arms attempted to wrap around his body and pin him, and with a shock, Satan realized he could _feel_ it draining his blood. He screamed as loud as he could into deformed ears and sank his knife into its back thrice before it let go, skittering to the ground with a spitting hiss.

Away from him, he could see that the creature resembled a large monkey with grotesquely long limbs and hooked feet. It looked deformed, missing patches of fur and with mismatched limbs and what looked like metal sticking out of it. It growled at him, his blood dripping off its long fangs, and Satan swore, bringing his knife up. Yukio was behind him, Yukio needed to be protected, Yukio-

The creature screamed as two bullets dug into its side and shoulder

-Yukio had just shot the creature, fire burning in his eye.

Oh right, Yukio wasn't really a child anymore.

Shiro ran in front of Rin without a hint of hesitation before the boy could try and fight a demon one-on-one ( _again_ ), pushing him back towards the other Exorcists that quickly formed a protective circle around the two boys. He paused, confusion obvious on his face, "Is that an _Asanbosam_?! Shit, that's a blood-sucker! Yukio check on your brother, _now_! We'll-"

Whatever plan the Paladin had went out the window when Kuro multiplied to the size of a small car, not caring that they were in a cramped alleyway, and pounced despite Shiro's protests- to which Satan had to agree with. The creature was small and built to grab and latch, so it wouldn't be hard for it to climb onto somewhere the _Cat Sídhe couldn't reach and rip open an artery or six. But Kuro was filled with anger and bloodlust at the sight of his charge being hurt so badly, and Satan wondered if he was going to have to call him back with some of his authority._

There wasn't a need, as the Asanbosam let out another spitting hiss and growled some literal nonsense in the demon language before scaling the steep walls like an overgrown spider and away from Kuro's claws. Shiro shot it at least five more times, but it seemed to be immune to pain and didn't pay it any mind, disappearing over the lip of the building. The Exorcists, predictably, scattered, leaving Shiro behind to guard Yukio as he did his best to patch up the nearly inch-deep bite wounds in Satan's arm, while the demon insisted he was fine. He had gotten the creature off of him fast enough it had only taken a few mouthfuls of blood, so he wasn't even dizzy. That didn't deter Yukio, who pulled out a rather larger first aid kit and set to work.

Satan hissed from the powerful disinfectant Yukio insisted on cleaning the wounds with despite his resistance to diseases, "The fuck was that monstrosity?"

"Asanbosams are blood-sucking demons that like to possess apes and monkeys. There shouldn't be any in Japan, but I'll bet that that was someone's exotic and likely very illegal pet." Shiro grimaced at the thought of just how much of a mess things could become if said owner insisted on finding their 'pet'. Hopefully, they could catch it and claim rabies if they needed. "How do you feel, Rin? You aren't dizzy, right?"

"I'm fine!" Satan growled to both the Exorcist and Yukio, but the boy refused to let go of his arm until he had wrapped it thoroughly in what was probably an excessive amount of gauze. "It barely got any of my blood. What's more important is that we get the hell out of here. We're too vulnerable." The walls were tall and practically a cage for them when against something that could scale them as easily as they could run.

"We should be fine. Asanbosams are ambushers, so I bet it's long gone." Despite his words, Shiro took up an obvious defensive position in front of the boys, Kuro still enlarged and growling at anything that moved, "Yukio, how bad is it?"

"I told you, I'm fine-!"

"You're a liar who has absolutely no sense of self-preservation just because you can take a couple more knocks to the head than most people. Now, Yukio?"

Yukio sighed and let his twin finally snatch his arm away. "It didn't pierce through his arm, somehow. There's some tearing, but I should be able to patch it up better once we get back. After that it should be fine because it's Rin."

Both of them had entered what Satan had dubbed "battle mode" effortlessly, all of their humor and carelessness draining away just because he got a little hurt. It would have been touching if Satan actually needed the care. Instead, it made him feel out of place, "You two can get pretty serious when you need to…"

And then, as one, the two said in perfect unison:

"Someone has to keep an eye on you."

"Gah, never do that again, it's creepy!"

* * *

Yukio unwrapped the bandages around Rin's arm and saw the wound- now several days old in appearance. Only a few hours had passed, and yet the bites had crusted over and the skin around it was cool and pale instead of red and irritated. By morning it would look over a week old and by this time tomorrow, the scab would probably start to peel away. The scar might remain for a week, but even that would fade within days instead of years. It might even be a bit faster since Rin healed small cuts completely in less than eight hours, and that was all the recent information Yukio had to go off of. It was hard to estimate as Rin continued to change.

"What, are you bothered by how I heal, Yukio?" Satan asked, poking the scab and wincing at how strongly humans felt pain. The healing was still horrendously slow compared to what he was used to, but surely this body was being forced to adapt to him and grow stronger.

A hand smacked his own away, "Stop that. And I'm only bothered because I know this will encourage you to be more and more reckless."

"Better me than you."

Yukio winced at the flippant way Rin dismissed such a horrific wound. If this kept up…"Don't say that, Rin! Just because you can heal fast doesn't mean that you should put yourself in harm's way! What if you lost that arm? Or what if it had ripped open your throat or crushed your skull or pierced your heart? What would you do then?"

Satan would heal, that's what would happen. And if he couldn't heal, then he would just pump more and more demonic power into his body until it either healed or the seals broke. It would be an anticlimactic way to reveal his secret, but if that's what it took to stay by Yukio and protect him, then he would do it instantly.

Of course he couldn't say any of that, so instead, "That's what I have you for, to patch me back up!"

"Rin, I'm not a miracle worker!"

"Not yet, you aren't. But you're amazing and I'm sure you would figure something out. 'I believe in you!' is the sort of thing I would say if I wasn't already sure you knew that damn well."

Yukio flushed and looked away from his brother's unnaturally blue eyes. He was too honest and blunt, "Rin…"

"It's fine. I decided I'll protect you a long time ago, whether you want me to or not. So, I'll be a human shield for you no matter what, so you might as well shut up and accept it."

"You're impossible."

"I'm stubborn. It's how I get the things I want."

"One day you're going to get in over your head."

He was "in over his head" the moment he was tricked by a certain woman and hadn't even attempted to surface ever since. Instead, he kept letting himself sink, even swimming deeper himself sometimes, and he hadn't regretted a second of it. Oh, he might regret some of the outcomes, but never once had he even attempted to pull himself free from the tangle he had made for himself. He enjoyed his little paradise that was built on lies and destined to fall to pieces too much to leave before he was hurt.

"As long as I'm by your side, I don't care." Satan repeated and saw Yukio frown but shrugged it off. "No matter what, we'll be together forever and ever! I promise, no, I swear it! Now, it's your turn, Yukio." Swear and promise until the greedy demon was sated for another day.

Yukio just sighed, "What are you, five? I'm not going to say something so ridiculous to someone who's probably going to get killed before they're twenty."

"But Yukio, I love you!" It was amazing how easy the words he had never had the courage to tell Yuri came now. But he knew that he had to express himself before it became too late. Yukio had to know, had to be sure in his very soul so that, maybe, when that cursed day came, he wouldn't hate him too much.

"Yes, yes, I know that. You say it so much sometimes I think you need to tone it down a little or people will get weird ideas." Yukio dismissed and walked away to put up the first aid kit, never really knowing his 'brother's' feelings, but that was fine. It was fine, because if Yukio could understand what Satan felt, then he would have had to suffer far too much, lost too much. Only when something was ripped away could you know just how important it was, but that was much to cruel for his precious child.

Yukio reappeared in the doorway, arms filled with books, "If you want to express how much you care for me without knocking someone's teeth in, how about you work on your studies a bit more?"

"Never mind, I hate you."

* * *

Somewhere, far away, a single vial of blood was presented to a certain scientist. It was something that had been long sought after every since a certain rumor had been confirmed by one of their newest agents. It had taken months to carefully acquire without raising the suspicion of the Demon King that had taken to watching the town, but it was sure to be worth it.

It was only a few ounces of red, but with it, history crumbled.

* * *

 **Time to see how many people read the manga.**

 **Also yes, this is the last chapter before they get to True Cross. It was originally going to be two different ones, but both were too short so I combined the ideas. It isn't the smoothest chapter, but honestly want to get to the good stuff. AKA executing the canon plot out back and dumping the body in the ocean.**

 **Disclaimer: It will take several chapters for said execution to happen, but it will happen. Also, expect longer chapter for the most part from now on.**


	26. The Demon's School

Chapter 25: The Demon's School

 **And so the real story begins. I'll still be skipping around a bit, mostly over things that happen the same, but hopefully this is a good start to show that I'm not just going to rewrite the arc 90% the same with only Satan's snarky commentary as the main difference.**

* * *

On the day they were due to leave for True Cross Academy, Shiro gave them a parting gift. Well, he actually gave them several (up to and including the sword that held Satan's powers, seals refreshed for all the good that would do), but this one was the only one Satan cared about. It was something he had craved and coveted for over a decade but hadn't been able to find even with the help of the internet's vast resources. He had given up any hope of finding it for the time being, only to have the damn priest drop it in his lap as if it were something simple. The only reason he wasn't holding it jealously to his chest was because Yukio needed to see it more than he did.

It was a picture of Yuri.

It wasn't a very good picture, slightly grainy and blurry with both age and the cheap film, off-centered and tilted a bit to the left. But it was still a picture of her, smiling daintily for whoever had taken what must have been a test picture. She was exactly as he remembered, with her wavy hair and big blue eyes.

"You have eyes just like her…" Satan muttered softly, barely restraining himself from brushing his hand over Yukio's face and tracing his moles, his nose, the tips of his ears, everything that was so much like Yuri. With her image before him, he could remember that cursed night, could remember his rage, but it had dried and washed away like blood.

"Rin…?" Yukio asked curiously, glancing over his shoulder where his twin stood, and Satan realized just how wistful he must sound.

He embraced the 'now' and poked Yukio's cheek, "Look, you have moles just like her!"

"Stop that Rin."

"But look, you even have the same number! One, two, three…" Satan listed, punctuating with a light tap only to fall short. He grabbed Yukio's face and started to examine it curiously, "Huh, I forget, do you have another one hidden under your hair?"

A hand sharply grabbed his hair and yanked him back Yukio could properly glair at him, "Your breath stinks, back up."

"Ahem." Shiro interrupted Rin's overdramatic whine, "As entertaining as this is, I do have something important to tell you both. You shouldn't show this to anyone else. In fact, I should have destroyed the entire camera when I found it, but I decided not to."

"They want to scrub her from history, don't they?" Satan filled in. It would explain why he couldn't even find a candid photo of her online, because the Exorcists had gotten rid off them all. He couldn't even be sure that they had kept a copy for their master records, though he _had_ had plans to search once he got free access. And if they were hidden away, well, he had always been good at sniffing out things that others tried to keep away from him.

"Yes, that's pretty much correct. It makes things easier for you two in the long run, but I think you two should at least know what she looked like."

Shiro, for all his supposed openness, still refused to tell he and Yukio the details of that wretched night, Satan noted. They had been told about the Blue Night, and Yukio was smart enough that Satan was sure he had at least put together part of the story even if he was keeping his thoughts to himself for now, but the shitty priest wasn't quite ready to confess that he had a direct hand in trying to murder Yukio's mother.

He probably wouldn't ever be, even as he raised her cursed children.

Satan wasn't ready to tell Yukio that story either because, no matter how much he hated it, Yukio cared for the shitty priest, and surely such a revelation would destroy him. He still wanted to tear down the shitty priest and have him confess his sins, have him admit that Yuri was both right and all that was righteous but…But it was different now. It was a different kind of hurting, a differing kind of revenge that ended with an apology and not a casket.

Satan knew he was going soft, but he didn't care.

Instead, he cared much more about the things he could have and change now. "Do you have the camera? I want it."

Shiro stared at him for a long moment, "Really? The camera doesn't even work anymore, and I've already developed all the pictures."

"I still want it. It was something she held."

And that was how Satan's most prized possession became an old, off-brand camera from the 90s.

* * *

Later that day, when the boys had reached True Cross Academy without incident and he had received plenty of reassuring texts from Yukio (and one brief one from Rin Yukio had clearly bullied him into sending), Shiro took out yet another picture. He had seen a lot over the past week as Rin had sorted through his excessive number of albums in order to find the ones he would take. He had obviously taken all of the ones from Yuri's camera, no matter how generic they were. All of them, except the one Shiro hadn't shown the boys.

It was a simple picture that had been near the beginning of the film that Yuri had taken of herself by accident- or at least, that's what anyone else would assume. Yuri was staring hard at the camera with obvious unimpressed confusion as she held it, a frown pulling at her lips and her pupils dyed red from the flash of the camera. That's how anyone else would see it, and maybe Shiro was just paranoid, maybe it was just the old film, but he swore her eyes looked a big jagged and distorted. A bit too blue.

Other than that, there was nothing remarkable about the picture. It was mundane, taken as a mistake, and nestled between pictures of both people and scenery. A mistake.

" _He really isn't what you think he is."_

A mistake indeed.

* * *

Satan hadn't been at True Cross Academy for more than a couple of hours before he realized he was being stared at.

Oh sure, he knew he had always had some admirers, but said admirers also knew of his reputation, and knew to keep away. Plenty of boys would try and talk themselves up, but they hardly knew what it meant to be an adult, much less a man, and so they fell behind him if they ever tried to follow. Some girls might gush about 'bad boys' but the moment they met one that wasn't all talk and teenage bluster, they fled. Which was good for Satan, because he really wasn't interested in being hit on by girls his youngest son's age. That was weirdly pedophilic, and Satan had a tendency to react violently murderous to those people. Yuri had at least been nearly twenty.

So yes, Satan knew when he was being watched by curious children who held a bit more than a passing interest in him. He just wasn't entirely sure how they already knew he was different since the opening ceremony had barely ended. Sure, Yukio, the first-year representative that he was, was getting plenty of attention in general, but Satan was nothing more than the genius' average brother. He didn't look that interesting since fighting the dress code was more trouble than it was worth (though his hair was getting a bit long again) and hadn't made any real waves. Not that he was planning to- Yukio had made him promise to "be good" and not pick any fights. He had managed to get Yukio to agree to spar more in exchange, so he was perfectly fine with the trade.

It took a few minutes and a few false leads, but he realized that the attention wasn't on him, but a tiny slip of a boy with black hair and blue-green eyes trailing behind him. For some reason people were fascinated by the unremarkable boy, probably because he was clearly trying to muster the courage to approach him like some girl and her crush.

Satan didn't give a flying shit about the gays despite what the church might try and say, but he really didn't want to deal with a confession on his first day.

It was best to just get it over with.

He whirled around too fast for the boy to escape into the crowd around them again and raised a brow, "What do you want?"

The boy froze like a mouse before a predator despite being noticeably taller than Satan's current body. He looked actually terrified, like he was afraid Satan was going to rip him apart, which, while flattering, was a bit annoying when he wasn't even trying to be intimidating. Hell, if he tried to actually pressure the boy then he might actually pass out!

"Well? I have to go meet up with my brother soon."

That seemed to snap the boy out of it. He swallowed, and Satan braced himself with a mental sigh, "I'm…My name is Minoru Tanaka, Rin, sir!"

Oh great, he had a stalker since he knew for a fact that he hadn't given his name yet. "Oh? And how the hell do you know my name?"

The boy, Minoru, tensed, "We've…met before once before. It was a long time ago and it was very brief, and you were…b-busy 'handing' some bad people," Minoru strutted, shivering for some reason Satan couldn't fathom unless he got queasy at a couple of punches, "And I was just hoping that you would…remember me. But I guess not…"

Satan actually had a very good memory, but he had learned to be selective about what he did and didn't remember. One thing he did remember was at least the face of every people who had ever started a fight with him who he had a feeling would be a repeat offender and give him trouble later down the line. He also tended to remember who he may have protected intentionally or otherwise so he knew who he could later cash in favors with. And Minoru wasn't ringing a single bell.

"I can't say I remember you at all." Satan said and internally winced as he saw the boy visibly wilt at that. He looked too much like a younger Yukio when he did that, "Look, whatever shithead bully's head I was kicking in," Satan drawled as if he were bored, though he didn't miss how Minoru shivered yet again. The kid just could not handle any violence, yeesh! It wasn't like he actually murdered petty playground bullies, "just know, you don't 'owe me' or anything. I didn't do it for you."

"I know that, just…" Minoru took a deep breath and bowed, "Thank you very much for saving me!"

Minoru ran away before Satan could even say anything, which was probably for the best. He really didn't know how to handle other kids misinterpreting his actions and pretending that he did the things because of them. Minoru was hardly the first kid to do such a thing, but it hadn't happened in a while.

"'Saving me', huh? That's a bit overdramatic."

What a weird kid.

* * *

"I would love to join you two on your first day in cram school, but alas, I have more important matters to attend to! Just use that key in any door!"

And that was how Samael essentially abandoned Satan and Yukio in the middle of True Cross Academy with nothing but two keys and vague directions, disappearing in a flourish of pink smoke. Satan refused to sigh and instead investigated his key and wondered just how san Samael even was to be passing around artifacts like this like cheap party favors. He could practically smell the magic coming off it and it was a wonder it didn't explode like a bomb in his hands!

Yukio sighed at Rin as he held the key at arm's length, looking at it like it would come alive and bite him, "Come on, Rin, or we'll be late."

"Fine, fine…" Satan huffed, finally determining that the key's magic was perfectly inert unless something drastic happened. He sharply whistled, "Come on, Kuro."

" _Ok, Rin!"_

Yukio unlocked the door to what looked like a random storage closet and blinked at the change in scenery. It wasn't like he had doubted Mephisto, but it was something else to see how the keys worked for himself. No wonder Shiro could do missions and still be back in time for dinner. "You still have that special permission form for Kuro, right?"

"Right here." Satan assured, holding the door open for said _Cat Sídhe and lightly nudging the small demon when he started to get distracted (again),_ "But what we should really be worrying about is that…uh, Mephisto didn't even tell us what classroom we have."

"Don't worry, I checked and it's 1106. Come on, we don't want to be late."

Despite the long hallways they arrived at the door they needed quickly- the key had to be programed to drop them off near there then. Satan would have to make sure of that later and see if they would exit out the same door they came in or not. Otherwise, things might become difficult for them.

The hallways were impressive and overly grandiose with stupidly high ceilings that would be perfect to hide it if needed, but the classroom itself was…less so. The room looked like it had been hastily cleaned and was, well… "Man, it sure is empty here. There's…" Satan did a quick head-count: two girls who were sticking together, a group of three guys, and one freak with a hand puppet sitting all alone. "only six other people here."

Yukio stepped forward, "Hello there, my name is Yukio Okumura- Yukio is fine. This is my brother, Rin. I hope we can all worth together this year."

The small bubbles of conversations screeched to a halt as Yukio stood there, forced smile twitching a bit as the occupants stared at him. They had all clearly formed their own social groups already, but Yukio had thrown a wrench into that. After all, if they were to be working together to fight demons, then they had to at least know each other's names and get along well enough that no one would just let someone else die. It was that mindset and initiative that had let Yukio become top of his class when others would have backed off after all.

Finally, one of the girls, nervous looking and with brown hair, stood up, "Um, I'm Noriko Paku, please call me Paku. It's good to meet you too, Yukio."

Earnest, but Satan could already tell she was weak. Physical strength didn't matter nearly as much as mental fortitude, and this girl clearly lacked both, even if she seemed fairly nice.

The girl next to her rolled her eyes and didn't bother to stand up, "I'm Izumo Kamiki. Hi, I guess."

Satan instantly knew that that girl was going to be difficult to deal with. There was something wrong with her, yeah, but like hell he was going to let her potentially get Yukio hurt just because she was in the middle of some shitty teenage angst. He seriously doubted that she had any serious problems in her life and was just being a brat because she could.

One of the three guys perked up- the one with oddly pink hair, "Hey there, I'm Renzo Shima, call me whatever you want! By the way, I love what you've done with your hair, Rin."

Satan blinked and looked at his hair to notice the slight blue tinge that had crept into with him noticing. And not 'blue in certain lights' but actually a very dark blue just a shade too bright to truly be black anymore. Well, that couldn't be a good sign and it was surely going to get worse as it lightened more and more to reflect his demonic self. "Thanks, I wanted to try something, but nothing super crazy just yet. I might change it later." He might as well cover his bases for the future in case he woke up an albino.

"It's probably a good idea to be cautious like that. I wanted red but the dye failed, and I ended up getting pink. But I kind of like it, so I've kept it that way ever since."

The boy with the dyed hair spoke up with a grunt, "I'm Ryuji Suguro"

"K-Konekomaru Miwa." The short boy (who had shaved his head for some reason) stuttered out, not wanting to be the odd one out.

Satan didn't bother evaluating the other two boys other than generic statements like "tough-guy" and "small, nervous" because Renzo was a bit off. It wasn't anything major, but the boy felt fake in a way. Nothing that really set Satan's instincts off, but just enough he could tell that he had an ill-fitting mask in place. Fakes were good at spotting fakes, so he would have to be a bit more careful around him.

"And you? Excuse me, what's your name?"

Oh, it looked like Yukio was trying to get the loner with the puppet to speak up, to no avail. Now that was a boy who set off something deep inside Satan. Satan was bad at gauging other's general abilities beyond if he could take them in a fight or not (the answer would, without fail, become yes if enough time passed) but even he could tell that that boy was powerful, too powerful to be in a classroom like this. The other humans wouldn't be able to tell, but the boy smelled too strongly of mid and higher demons to not dabble with them regularly. Satan would bet that he was here on Mephisto's orders, probably to watch 'Rin'. He would watch him, but it was unlikely the boy would do anything for a while, if ever.

In the meantime, he watched as Yukio tried to get the stoic boy to respond.

"Excuse me, but-"

"Don't you get that if someone's silent they don't want to talk to you, or are you just too stupid understand?" The puppet on the boy's hand snapped.

Alright, all bets were off now, "Hey, you trying to start something, asshole?"

"Easy, Rin." Yukio reassured, one strong hand on his shoulder and the other petting Kuro (who had jumped on the table) to calm him as well, "If he doesn't want to interact, then we can't force him."

"Whatever." Satan grumbled and scooped Kuro up to follow Yukio to a desk in the front row. He really hated being in the front, but he didn't have much choice if he wanted to plant himself firmly between the weirdo probably-a-spy's direct line of sight and Yukio.

The twin-tailed girl, Izumo, stared at him strangely, "Isn't that a _Cat Sídhe?"_

Satan lazily waved the paperwork given to him earlier, "Yeah, but he's mine. I have a form for him and everything."

"But why-?"

Yukio coughed and made a point of blocking Kuro from Izumo's sight, "Wasn't class supposed to start before now?"

"Yeah, we were!" Renzo piped up from across the room, "And aren't we allowed to leave if the teacher doesn't show up or something?"

Satan groaned, "That's only a stupid and shitty rumor. Trust me, I've tried."

"You sure do swear a lot…" The pink haired boy muttered with a small laugh.

"If you have a problem with how much Rin swears, you should do your best to make peace with it now." Yukio explained with clinical detachment, "Trying to get him to stop is hopeless, like a lot of things are with him."

"When the hell did you get so mean, Yukio?!"

"See?"

Renzo really did laugh at that, "Oh no, it's fine, really! If I had an issue with that, I wouldn't hang out with Bon."

"The hell does that mean?"

"See?"

Before things could escalate anymore the door to the classroom slammed open. In rushed an older Exorcist with ridiculous sideburns, arms filled with supplies that he barely managed to set on the table before they could tumble out of his hands. Yukio made a gesture to help, but Satan stopped him. It was one thing to take the initiative to try and make everyone get to know each other, but he would lose any respect others might have if he looked like a teacher's pet, never mind how ridiculous that mindset was.

The man spoke up after he had collected himself, "Hello there, my good students, my name is Kaoru Tsubaki- You all may refer to me as Mr. Tsubaki! Sorry for being tardy, I had other _things_ to attend to first, but…"

The door, never properly closed, drifted open again, and yet another person appeared, poking their head into the room.

Satan did not expect to recognize this person. In fact, he didn't know what the actual _fuck_ Amaimon was doing in an Exorcist stronghold. His hand drifted to one of his concealed knives and he tensed, ready to spring at a moment's notice. Hell, he might have to break the seal on the sword he was now very glad he had been nagged into not leaving in his new dorm room if things got bad.

Amaimon, oblivious as always, shouldered his way into the room. His arms, as well, were filled dangerously high with heavy-looking metal equipment and boxes. "I'm here with the stuff you wanted…Oh. This is…the wrong room, isn't it?"

A hand reached out from the hallway and carelessly yanked the Demon King back. Amaimon let it happen, though for a second his eyes met Satan's curiously, and with obvious purpose. There was no sudden recognition, no exchanged thoughts through that look alone or anything, but Satan _knew_ that he had just been evaluated. Sized-up, and probably for a future fight knowing Amaimon's violent tendencies.

A scruffy looking man wearing an off-brand safari hat stuck his head in with a laugh, "Sorry for that folks, please excuse my companion here, he's a bit…ah, you know…"

"I'm a bit like what?"

"I think I'll omit the rest for now, haha!"

The man ducked back into the hallway, taking care to close the door properly. Satan waited, but no sounds of violent murder echoed from the hallway, so either that human actually could handle Amaimon or he was satisfied with his trip for now.

Not for the first time, Satan wondered just how stupid Amaimon actually was.

"Ahem," The teacher began, trying to regain control of his class, "now if we could get started?"

"Hold it, hold it!" The punk, Ryuji something, shouted, standing up sharply, "Wasn't that Arc Knight Lewin Light? What's he doing here?"

Lewin Light, what kind of unfitting name for such a shady looking man was that? Well, at least him being an Arc Knight explained why Amaimon hadn't broken his spine yet, even if he hadn't gotten the memo that said Demon King had officially joined the Exorcists with Samael.

Kaoru tried to explain as quickly as possible, "He's been designated handler of Amaimon, who is who you saw with him. Now, I'm sure you all have a lot of questions…"

"That was the Demon King Amaimon? I hear he's supposed to be super strong, but he really didn't look it."

"I still can't believe that they've decided to trust yet another Demon King…"

"Isn't it obvious?" Izumo sneered from the back, interrupting the surge of whispers before it could even properly begin to swell, "Things are clearly way worse than they want to let us know because they think that that will scare us off. Like I'm that weak! I know what I'm getting myself into! The fact that the schedule for this year is a lot more intense should have been enough of a hint anyway."

"I know all of you have a lot of questions, but as Ms. Kamiki pointed out, our schedule is much more intensive this year! So, we should get started now, shouldn't we?" Kaoru said, waiting to see if anyone would raise any more objections. "Good, good. Now, who here hasn't received a Temptaint?"

Satan stopped paying attention after sans taking note of which humans had been foolish enough to try and fight demons without even seeing them before. Instead, he ignored the gasps at the revelation that there were goblins in the room (he had felt them in the shadows, but they were tiny and weak and not worth his time) to instead try and digest all that he had learned in the past few minutes. Amaimon was openly working with the Exorcists which meant that big things had to be happening to force that of all things. It probably had something to do with Gehenna destabilizing, though he couldn't be entirely sure until he was actually given more information. There was also the fact that-

There was a goblin on his desk, no bigger than his hand, and it was clearly eyeing the way his hand idly twirled his pencil. He rolled his eyes even as someone gasped at how close it was to him and flicked its nose without a care for how wild the animal blood was driving it. It hissed angrily at him and so Satan growled back, easily catching the hand that made to swipe at him.

"Hey, stop that."

It hissed at him and tried to bit him. Annoyed, Satan jabbed his pencil into its mouth and let it stumble away and gag.

" _Rin, can I eat it?"_ Kuro asked, looking hopefully up from the floor.

The goblin hissed again and, fed up, Satan snatched it off the desk, grabbing it by its back and rendering it helpless. It flailed for a few seconds before giving up and going limp. Happy that it had finally calmed down, Satan set it down on the floor. "Kuro, don't eat it or something. It'll give you a stomach ache if you do."

" _Aww…"_

He nudged the goblin with his foot until it got the message and tottered back to wherever it had come. Honestly, he didn't care much if it lived or died, and if it attacked Yukio then he would have shredded it on the spot. But it had been purposely driven into a blood frenzy by the Exorcist, so it left a bad taste in his mouth to kill something that was basically a victim.

"Wow…"

It looked like he had an audience, with every single person in the classroom (including the puppet boy) watching him with wide eyes. What were they so impressed with, it wasn't like goblins were even that dangerous! They were naturally pretty docile, so if you just held them down for a bit they would calm from even a forced bloodlust! Seriously, it wasn't any different than handling an animal! Even the teacher looked surprised, and he should know damn well that most demons tried to _avoid_ humans!

"What? Goblins aren't that aggressive, and you're the one who made them frenzy, Mr. _Teacher_."


	27. Classmates

Chapter 26: Classmates

 **When you try and write a serious chapter, re-write one part 5+ times, then scrap it and throw in some nonsense instead because there'll be plenty of drama later. Also I'm sick of this chapter and kind of just want to blow through cannon,**

 **AKA Satan unintentionally ruins Bon's dramatic introduction chapter by virtue of simply existing. Not that that's anything new.**

* * *

Classes were progressing smoothly enough, even if the Exorcist ones were so boring Satan wanted to skip them all together. But that would be leaving Yukio all alone in an Exorcist stronghold, so he would put up with them, as tedious as they were. Most of the information they were covering in the first couple of days was so basic Satan could recite it in his sleep, while the rest was outright wrong. Some of it was clearly the Exorcists misinterpreting demon behavior, but at least part of that had to be due to the fact that they had a grand total of two teachers for half a dozen different subjects. Sideburns had grieved for his free time with his "kitten" enough times that Satan realized just how shorthanded they were, to the point that Kaoru was stuck teaching everything but summoning and Aria-related classes. Their other teacher, Igor Neusomething looked equally displeased that he had been drafted to teach something beyond his specialty and seemed to serious dislike Satan. And Satan meant both himself as Rin and the Satan the Exorcists had been at unofficial war with for a couple thousand years now.

He was the primary reason Satan refused to leave Yukio alone for even one class. Sure, Igor's general distaste for him seemed to stem from the fact that Satan made a piss-poor Aria for obvious reasons (the chants couldn't really hurt him, but they felt wrong on his foreign tongue) but that didn't mean he was going to take any chances.

Now if only Yukio would let him sleep through class. Yes, he could just move, but the boy had scarily accurate aim and a poker face that would do Satan proud if it hadn't been used to reassure him that no, Yukio really didn't know where all his knives kept vanishing to, honest, don't you trust your brother?

Damned puppy-eyed brat.

The only even remotely interesting thing that ended up happening was when another girl suddenly started attending class, bringing the classroom's size up to the grand total of nine students, and even that excitement was short-lived-

The girl, blond and looking incredibly uncomfortable in the school uniform's short skirt, was a timid thing who could hardly raise her voice, "Um…Um, are you Yukio Okumura?"

Yukio was kind enough to humor the weak girl, "Yes I am. Shiemi, was it?"

"Yes! Since I decided to become an Exorcist, Mr. Fujimoto told me that you might be willing to, ah, help me adjust?"

Satan, busy playing with Kuro all throughout the girl's introduction, perked up just enough to roll his eyes, "He's already trying to set you up, huh?"

Shiemi's face turned bright red and she sputtered, "S-Set up?! I'm sorry, I'm not- I can't-!"

"Please ignore him, Shiemi." Yukio said airily, and no one would ever know that he was pressing a pen to Satan's thigh in a clear threat, "My brother doesn't have the filter most people do, and so he says whatever he can think of. I'm sure that Mr. Fujimoto just wants me to make sure you stay caught up with the class, right?"

"Y-Yes! Exactly that and nothing else!"

If she kept nodding that fast she was likely to pass out, Satan noted and leaned forward just enough so he could catch her scent better. She was naturally strong for sure, filled with spring strength that reminded him a bit of Yuri's summer fortitude. Almost surely a future tamer with the way her energy swelled and beckoned him (however incompatible it was), but she was such a small thing that would probably be consumed by whatever she tried to contract with.

"Whatever. It's not like she's good enough for you anyway."

Shiemi shrank away at his words, the perfect image of a wilting flower and doing everything in her power to reaffirm his thoughts on her.

Yukio sighed, "You're hardly a good judge of romantic partners, considering how you literally scare girls away. And would it kill you to try and get along with the class a bit more?"

"If they can't handle me at my worst, then they don't deserve me at my best…or whatever that phrase is."

"…You're going to be alone forever, Rin."

The annoying teacher cleared his throat to force silence before anyone could get into another argument, "I know that a new classmate is exciting, but we're already behind! Please sit down, Ms. Moriyama."

"Right!"

* * *

It probably wasn't fair, Yukio mused, but Shiemi was forced to take her first test that very same day. Mr. Tsubaki had noticed and offered to let her sit out the test, but Shiemi has adamantly insisted that she would like to "become part of the class" as soon as she could, confident in her ability to do well on a demon pharmacology test. And now, from what little Yukio could hear, she was probably regretting it. He could practically feel the stress rolling off her in waves from where she sat directly behind him, her mummers growing more and more worried.

It looked like he really was going to have to insist on helping her. Especially if his dad was counting on him, and Rin would just have to deal with it. In fact, it was probably

Unsurprisingly, Rin was the first to finish and turn in his test. No matter the subject, without fail, Rin would always be one of the first to turn his test, chronically allergic to the idea of checking his work. And, as was becoming more and more common, the moment Rin sat back down he took the chance to nap. Yukio knew just how beneficial a power nap could be, but he really had to wonder just how much sleep Rin was actually getting.

As Yukio turned in his own test, he spotted Ryuji, or Bon as he liked to be called, glaring over the edge of his own test at the sleeping form of Rin. Yukio was still getting a read on the class as a whole, but he could already tell that Bon was a hard worker, despite his honestly punk appearance. He clearly kept both his body and mind sharp and was the undisputed best Aria in the class already. And so, to see someone like Rin seem to not take anything seriously while still coasting along on average to decent grades…

Ah, it looked like Yukio was going to have to make sure Bon didn't get in over his head when, twenty minutes later, Bon, once again, paraded up to Rin's desk and happily showed off the results to his demon pharmacology test the moment the teacher stepped out for a 'break': a 100 to Rin's 81. And sure, it wasn't close to how neck-in-neck their scores sometimes were, (Rin had almost gotten a perfect score on their first demonic studies test, missing points only for misspellings) but it wasn't as if Rin had done particularly bad either. Rin looked deceptively passive and calm, watching as Bon went on his little rant about work ethic, doing nothing but staring and not even trying to interrupt. But it was the calm before the storm, and Yukio could see Rin drawing in like the sea before a tsunami, slowly coiling up to lash out with his own vicious words.

"…And maybe if you would spend less time talking shit about others and just looked at yourself, then you would actually-"

It was about there that Yukio could see when Rin had had enough, "See, that's great and all, but Ryuji….No, Bon. Yeah. Bon-bon," Ryuji squawked and Shima nearly choked holding back laughter. Even the usually quiet Konekomaru looked a bit amused at that. Well, they could laugh while Rin was still playing nice, but Yukio had seen him rip apart Shiro often enough that he knew what was coming, "See, I'm not your disapproving father, or those people who laughed at you when you were a kid, or that one girl you couldn't ever impress, or whatever deep-rooted and I'm sure oh-so tragic backstory you have. I'm just guy, some punk who's opinion honestly shouldn't matter this much to you that-"

Yukio cleared his throat, a firm hand on his twin's shoulder pushing him back into his chair, "Rin, that's enough."

"I'm just behind honest." Rin justified without malice, and Yukio knew, that while he may have been aiming to hurt, he could have done much worse, "This guy keeps trying to prove how great he is, and it's disgusting how he doesn't even realize how pathetic it looks. How do you think the people who did even worse on this test than I did feel, huh?"

Behind him, Shiemi, who had been cringing away from Rin's mean words shrank back away for an entirely different reason, trying to hide her mid-40s test to her chest. Paku grimaced at her own 85, a sharp contrast to Izumo's 96. Even Shima laughed nervously at his 75 when Bon looked at him in horror.

"Shima, if you were struggling I would have gladly helped you!"

"Ahaha, I mean, it's not like I'm training to be a Doctor, so it doesn't really matter…?"

Rin huffed, picking Kuro up from the floor and started petting the cat, like some sort of cliché villain, "Learn to read the mood a bit better before you start trying to get into a pissing contest."

Yukio saw the chance and took it before a real fight could break out. Now that Bon was cowed for at least the moment as he realized his blunder, he could try and fix things. "While I think Rin always goes about these things in a too-direct manner, he is right- you can't expect everyone to always be at your level or to share your feelings, Ryuji. However, in the interest of keeping things amicable between classmates, I think the two of you should apologize to each other."

Rin sneered before Bon could even open his mouth, "I didn't do anything wrong, so I'm not saying sorry. Of course, I'm not going to hold your ego over your head or anything, so I won't let you die at least, _Bon-bon_."

"You-!" Bon shouted, and Yukio had only a moment to grieve the death of all hopes of a properly collaborating class, "You really are just some brat! Why are you even here? Everyone else is here because they're serious about being Exorcists, but you don't even try to apply yourself!"

"I'm here because Yukio is here so I can keep an eye on him. Why, does your reason tie to why you're so obviously insecure?"

"I'm going to kill Satan for what he did on the Blue Night!"

It was silent as everyone stared at Bon with wide eyes. His friends didn't look too surprised, but everyone else needed a moment to process such a bold claim. Kill Satan? But how was he supposed to do that when Satan was…

Rin sputtered for a long second, almost choking, and then nearly fell out of his chair with laughter, "Ahahahaha! That's great, you've actually got a sense of humor there!" The dead silence and Bon's growing rage made the other teen blink, "Wait, you're serious? You're actually serious!? 'Kill Satan'? You?"

"Don't you dare laugh at me, I'll do it!"

"Pff, yeah, good luck with that." Rin laughed again, dismissing Bon like he was an unruly child, "First, you'll have to…ah, well, actually be a threat?"

While Yukio was glad his brother had remembered at the last second that Satan's disappearance was supposed to be classified, this wasn't exactly a smooth save. Bon growled lowly at that and for a second it looked like a fight was going to break out on the spot. So Yukio stepped between them, holding up his own test (a perfect 100) so everyone could see it, "Since it appears that some of our classmates are behind, wouldn't it be best if you, Izumo, and I helped to tutor them, Bon?"

Izumo scoffed, loud and clear despite being on the other side of the room, "You really are determined to try and make everyone play nice? It's annoying and pointless to try and make idiots to try and get along."

"Regardless of what you think, you're only guaranteed to fail if you never try." Yukio said calmly, swatting down Rin's hand before he could flip her off without even looking. He pulled out the relevant books and notes and laid them on the table, "If anyone would like to copy my notes you're free to do so, though I think we'd all be better off setting up study sessions. Our workload isn't exactly light, so it might be difficult to balance our normal studies and Exorcist studies otherwise."

Rin grumbled but obediently began to look over exactly what he had gotten wrong on his test, ignoring the comments about how "whipped" he was. Comments which quickly ceased when Yukio smiled in a way that was frankly terrifying at the Bon-bon trio (a nickname he would only use in the safety of his own mind), "Well, Bon, aren't you going to help your friends?"

It was a loaded question and they both knew it, but Bon complied with a grumble, roughly dragging Shima into his chair and pointing out every single thing he had gotten wrong. Konekomaru followed with a laugh after a second, all while the puppet-handed boy kept to himself.

And now for the problem case…"Shiemi, I'll help you personally if that's alright?"

From what he could tell, Shiemi was skittish and nervous around so many people, so Yukio did his best to smile as disarmingly as he could. For some reason, her face flushed bright red and she nodded, clutching her test in front of her. Her words were more of a squeak than anything, "Y-Yes…"

Rin groaned, and Yukio ignored his brother's melodramatics.

"Whatever." Izumo muttered, but Yukio could see her pointing out to Paku what she had gotten wrong and why as he sat by Shiemi.

* * *

Mr. Tsubaki was turning an interesting shade of red, Yukio noted from where he sat patiently on the side, watching the drama unfold that was their physical education class. Really, he should have expected this considering the 'presence' his brother had. Usually, it was a good thing, but in some cases…

"Rin Okumura, whatever you're doing, stop it!" The teacher shouted, futilely.

"I'm just looking at it!" Rin, the only one still in the pit, shouted back, looking away from the suspiciously still Leaper demon. And…nothing. Easily three times his size, and yet it refused to move the moment Rin had looked at it. "It's not my fault it can recognize its betters! And what kind of shitty exercise is this anyway?!"

"Detention!"

"What the fuck for?"

"For your foul language! I've warned you to at least tone it down enough times already!"

"Oi, you don't need to take it out on me that you aren't getting enough time to screw your girl!"

"You-!"

Renzo whistled, low and appreciative at the shouting match that would delay class for at least ten minutes if past experience was anything to go by. "Wow, Rin really is something else…" It took guts to cuss out a teacher like that. A lot of people would think he was just being foolish, but considering how casually he was taking everything…

Konekomaru nodded, eyes wide. "He isn't scared at all being so close to a demon, huh? Well, he does have a _Cat Sídhe_ as a familiar."

Kuro meowed appreciatively, tails flicking happily as he watched the Leaper below carefully, just in case. Whereas Kuro could respect how strong Rin was, the Leaper was weak and terrified by him instead. Or at least, Yukio assumed that was what was going on, but he doubted the rest of his class would understand. Once it had become clear that the Leaper wasn't going to chase Rin, he had been forced to sit out the exercise until everyone else had completed it- a task in and of itself considering how much Rin had protested the idea of Yukio being left alone near a demon. And then he had been quickly shoved into the pit where a hopefully near-berserk Leaper would finally chase him.

Of course, the demon had stopped dead not ten feet from the teenager, and it hadn't moved since. Yukio knew Rin didn't need the experience, but he wasn't about to explain that his brother had been hunting much more nimbler demons such as ghouls ever since he was ten.

Bon was more confused and frustrated than impressed. Ever since Rin had shown up, things had started making less and less sense. He had wanted to prove he was better than Rin, but that was kind of hard to do when any chance of that happening had evaporated. "Leapers are supposed to attack if they sense any sort agitation or you break eye contact, but that guy is seriously pissed off and isn't paying attention, and it isn't doing a thing."

Shimei shifted nervously from where she sat, "I guess that means Rin is really strong and confident, right?"

A feminine scoff, "Or an idiot who's so stupid the demons are just smart enough to not eat him, lest they catch his idiocy."

Yukio, so used to the chaos that was Rin butting heads with reality and logic, had pulled up a list of Arias to study until things cooled down. With disinterest he glared at Izumo, hardly giving her a second-long look before going back to his work. "Rin is anything but stupid, and it would show if he bothered to check his work more. Even then, I have no doubt he'll be the top of the class in any practical fields because he's just that strong." Despite his words, Yukio smiled fondly to himself.

Paku smiled with just a touch of strain, "You really do, uh, respect your brother, don't you, Yukio?"

"You don't have to try and sugar-coat it, Paku." Izumo huffed, looking down her nose at Yukio like he was a pest, "I thought the brother-complex thing only went one way, but it looks like it's a two-way street. Before you know it, they'll be doing disgusting things together."

With a _snap_ , the notebook closed, "I don't like what you're implying, _Ms. Kamiki._ "

"I'm just calling it like I see it: your brother is way too attached to you for it to be normal. We've only had class for a week and he hasn't left your side, and you just keep encouraging it!"

And that was the problem, wasn't it? What had once been a constant comfort had become an annoyance at best, and the prelude to a serious problem in the future. 'Attached' wasn't a strong enough word for the way Rin would practically lose his mind if Yukio was even slightly uncomfortable…"I know what you're talking about, and I'm doing my best to try and let Rin know that he doesn't need to protect me anymore…"

It was more like dependence.

Izumo, however, wasn't finished, "Yeah, well you're doing a pretty terrible job at it. It's pretty obvious he'd do anything for you, and I do mean _anything_. That's not good, you hear? One day he'll…Well, whatever, who cares."

Yukio felt the bubbling anger drain out of him quick enough it left him dizzy and light. He could feel the other's hackles rising on his behalf, could feel Shiemi grow more and more worried behind him, but he hadn't grown up with an emotionally damaged brother (when and how it happened, Yukio didn't know, but now that he was better read he was sure that was what was wrong) and not learned to read someone's true intent, under a mask.

Yukio, instead of lashing back, smiled. "You're just a bit kinder than you like to let on, aren't you, Izumo?"

Izumo's face turned red so fast it was amazing she didn't pass out from it, "Wha…What are you-"

Ah, but it would seem Yukio was just a bit cruel in his own way, and he couldn't stop himself from pressing his advantage just a _little_ bit more, "You're a bit like my brother in that way, you know. Both of you don't-"

"No!" Izumo shouted, sharply standing and pointing accusingly at Yukio, "No, you are _not_ comparing me to _that moron_!"

Rin's head snapped up to glare at the shouting, "Oi, twin tail bitch, what are you saying to Yukio!?"

"T-That's none of your business, you brother-complex freak!"

"Whore, I will hang you by your pigtails!"

"Get mauled by a demon already!"

"You-Sonofa-!" Whatever Rin had been going to say was cut off as the Leaper finally decided to attack him. The move was so sudden that Mr. Tsubaki didn't have time to react before it landed…exactly where Rin had been a second ago. But the teen had leapt to the side, caught the Leaper's collar, and swung himself so he sat on its back. The Leaper, of course, immediately began to struggle, but Rin had managed to secure himself to it with an arm looped under its collar, while the other…

Yukio hadn't been scared when the Leaper had attacked, but his heart seized when he saw Rin reach for the sealed sword he had finally convinced his brother to carry around and protect. Was he going to draw it in a fit of irrational anger, was this how everything would end, to a low-level demon?

Of course not, because for Rin to draw the sword he would have had to actually feel threatened. And a demonic frog the size of a car clearly wasn't going to faze him after he had scoffed at Astaroth. No, instead Yukio felt his blood pressure rise as he watched his brother use a sacred demonic sword as a crude club to beat the struggling Leaper upside the head. Repeatedly. An excessive amount, really.

It wasn't until the Leaper stopped trying to throw him off that Rin also stopped, slinging the sacred sword-turned-beating-stick over his shoulder with a grin. "There, now was that so hard? Now be good, damn it." He noticed his audience and frowned, "What?"

Even Yukio wasn't mad when Mr. Tsubaki finally jerked the Leaper's chain back, sending Rin into a spectacular faceplant as his mount was swept out from under him.

Izumo watched the teen shoot to his feet and start swearing up a storm at the teacher…again. "I take it back, Rin isn't an idiot, he's mentally retarded. He fell on his head a lot as a kid, didn't he?"

Yukio's silence as he stood to help treat Rin's bloodied nose (almost surely broken, but something like that couldn't heal overnight) was all the answer they needed.


	28. Projects

Chapter 27: Projects

 **After spending way too long thinking way too hard about this story, I realized I was taking this far,** ** _far,_** **too seriously. This is fanfiction, I should just write and worry about if it makes sense after the fact. I don't write for the reviews (my personal passion project gets like 1/10** **th** **the attention of this crack story, but I've already written more for that than this) but I won't lie and say that seeing them isn't a nice bit of motivation and helped me remember myself.**

 **So I've had a couple of people ask about the other "Rin is Satan" fics I was referring to. First and foremost is Revelations Paradise Acquired by** **Shinigami of the Elder Gods,** **which is, unfortunately, the only one I can still find. It was by far my biggest inspiration, though sadly it is also very much dead, and right when things looked like they would pick up. There was also ef07's Blue Fire (who now goes by MightyGoat), but that's been deleted and I've only ever managed to scrounge up a couple of chapters to confirm it once existed through some archive shenanigans, and even those have some serious gaps in them. Those are the only other two I know of, but if anyone has any others, feel free to share them.**

* * *

It began as many things do- with an inconsequential offer to help tutor Shiemi. An offer that Yukio was taken up on by the end of week as the girl realized just how behind she was. An offer that he very much did not remember extending to anyone else, but was now somehow the host of group study sessions with over half the class. Apparently, Shima was doing especially poor in certain classes while Konekomaru simply wished his grades matched Bon's near perfect scores. And because he was already helping Shiemi, that somehow translated to him being the tutor of the class. Even Paku dropped by on occasion, dragging Izumo with her. Neither Bon nor Izumo actually needed any real help, but both of them were fairly…poor teachers. They were borderline geniuses, either through natural talent or sheer hard work, and so they couldn't quite understand why their classmates found certain things difficult.

Obviously helping so many people took its toll on Yukio's free time, and so Rin was finally forced to attend if he wanted any help. Honestly, if Rin was willing to put in any effort at all into school, Yukio had little doubt that he would be the top of the class. He could identify most demons and their traits with just a glance, knew a shocking amount about medical plants despite Yukio being sure he had never even cracked open that textbook, and had memorized plenty of arias despite disliking reciting them. He just simply lacked the motivation to do anything more than the bare minimum for school.

In fact, he seemed to lack the motivation to do more than the bare minimum in most aspects of his life. Despite his attitude, despite his energy, Rin never seemed to want anything for himself in life. Oh sure, he would devour plenty of good food and soak in hot baths, but he held no aspirations for himself. Everything in Rin's life circled back around to Yukio.

Yukio resisted sighing at the thought, knowing that Shiemi would think that she had done something wrong. And a small part of him _did_ want to sigh at just how far behind she was. Not just in Exorcist classes, but her general education was severally lacking as well. Even now after everyone else had moved on to another assignment, Shiemi was still struggling with her medial herb homework. She had made good progress in remembering the actual names for the plants, but the math, as basic as it was, was a struggle for her. So, Yukio had decided to switch gears and help her with her math homework first. Well, he was trying to-

"And I say that your idea for the paper is _fucking stupid_. Who the hell wants to talk about the origins of region-specific arias for _fifteen_ pages?"

"Yeah, well I don't hear any ideas coming from you!"

"Because this entire project is stupid! Making it a group project doesn't make up for how ridiculously long it has to be!"

-but it seemed that his beloved brother was about to get into another fight. He was thankful that Paku and Izumo hadn't decided to attend today. It was funny in a sad way, as he seriously doubted that anyone would disagree with Rin, but his rather…colorful way of stating things tended to rub people the wrong way. Because the schedule had been compressed, several papers that should have been scattered throughout the year had been combined into one super-paper. They were allowed to freely collaborate and form groups of whatever size they wanted and choose any topic within the guidelines, but that hardly helped.

Yukio coughed very pointedly before things could continue to escalate. The picnic table they had spread their things probably couldn't handle Rin if he got…angry. "I believed that Bon suggested that topic because of how easy it would be to use quotes and pad the paper to reach the requirement. Virtually the entire aria could be quoted, along with different variants. Am I correct?"

The surprised look on Bon's face clearly said that he very much had _not_ thought of that idea, but the teen nodded furiously anyway, "Y-Yeah! Exactly that. And if you weren't so quick to be an asshole, I would have had time to explain that!"

The shorter boy scoffed, "Don't try and cover his ass, Yukio. But I guess that that'll work to fill out this shitty paper. So, Yukio, where do we start?"

An eraser pinged off Rin's head, but by the time he whipped his head around to glare, the very teen in question had started to collect his things. "I'll be sure to help later, but right now I've got to help Shiemi with the rest of her homework, as that's due tomorrow. But I'm sure that you, Bon, and everyone else can at least get some ideas down, right?"

Shima frowned, "Wait, are you really going to abandon us to this paper? That's a bit-"

Very suddenly the air was fridged. Nothing in Yukio's demeanor had really changed, but they were all very suddenly paying attention to his next words, "I've taken hours out of my own schedule to help all of you when the only person I promised I'd help was Shiemi. I didn't have to help any of you, but I decided to anyway. Now that I've done that, I'm sure that you all can get along and think of some things to write about while I stick to my actual promise, alright? Oh, and play nice, Rin." The smile he gave them as he ushered a flustered Shiemi to a different table was so pure and sincere that everyone was sure butter wouldn't melt in that mouth. No one tried to stop him from leaving.

Bon blinked as Rin practically collapsed onto the table, grumbling all the while. Shima blinked as the teen's arms suddenly entered his personal space, sprawled out across the table and all over his books. Trying to prod his hands away got him a sharp kick to the shin.

Covertly crossing his legs to prevent higher shots, Shima smiled as if he couldn't feet a bruise forming, "What's wrong all of a sudden?"

"Oh right, you idiots wouldn't get it." Rin grumbled from where he had buried his face in his open textbook, "Yukio's been trying to get me to 'make friends' for a while now, so I bet he left to try and force us to 'bond' or some shit…And if I don't try and 'play nice' with you idiots, Yukio will get mad at me…"

Bon stared into the sky and prayed to whatever god was listening for strength to deal with the brother-complex freak in front of him. He didn't like the idea of working with Rin _at all_ , but he and Yukio were kind of a package deal and he needed all the help he could find to fill out fifteen pages. "Oi, stop being such a drama queen. I don't want to be friends with a punk like you anyway, so you don't have to worry about that."

"Of course, you don't- you're barely worth being my underling."

Bon made a valent attempt to hit Rin with a book from across the table, but the teen's hand shot up and caught the paperback with eerie accuracy without ever looking up. Shima whistled lowly at that.

Konekomaru gently took the book out of Rin's hand before he could do something like chuck it into the trash. The teen sat up to glare at him, but it was so half-hearted that even he didn't feel threatened by it, "Guys, shouldn't we at least get started on the paper?"

Bon felt his brow twitch as Rin yawned loudly and looked ready to sleep as a method to ignore them, "Are you going to take this serious or not?!"

Rin blinked and looked across the table to where Bon sat. He stared at him for a moment with his eerily too-blue eyes before nodding once.

Good, at least they were all on the same page for once-

"I am completely serious about that vow of eternal servitude."

* * *

So, Shiemi, what exactly made you want to become an Exorcist all of a sudden?" Yukio said, ignoring the rising voices from across the lawn students often used to study at. It was better that they aired their grievances here instead of in the middle of an actual mission, or so he would keep telling himself.

It was strange that he had forgotten to ask, but Yukio justified that he had been busy dealing with Rin being, well, himself to new people. Which meant that he was stuck playing damage control to try and make Rin at least _seem_ human. So, he hadn't thought too hard about such an obviously shy girl suddenly decided to fight demons.

"I'm surprised that Mr. Fujimoto didn't tell you." Shiemi said with a slight tilt of her head as she thought about it a bit more, "Ah, I guess he has better things to do, so he probably doesn't even remember with how busy he must be…"

"Well, he was coming by to pick up a big bulk-order of supplies along with a few of his friends, but when he heard about how I wasn't able to walk anymore, he dropped everything he was doing to investigate! He realized what was wrong really fast and declared the entire garden a lost cause, so he started salting the entire place! He even, ah…" Shiemi paused, suddenly looking a bit sheepish, going as far as to look away from Yukio shyly.

"He even what?"

"He even said that your brother would, um…" Shiemi flushed, and Yukio smiled a little at how shy she still was at times, "…would like to help him burn everything…?"

That startled a laugh out of Yukio. Of course, his father would be unabashedly blunt when it came to Rin. Well, at least her embarrassment made sense now, "I'm not offended, Shiemi. How can I be when it's true?"

"Oh, so Rin really is like that…"

"Don't worry, he has it mostly in check nowadays." 'Mostly' actually meant the controlled burning of his old homework and garbage every couple of weeks, but no one needed to know that. Just like how they didn't need to know exactly how many knives Rin had squirreled away on his person at any given moment, "But, please continue."

"Right! Well, the garden was my grandmother's before she died…" And here Shiemi grimaced a bit, "…so I tried to stop him, but he wouldn't listen. Suddenly the demon jumped out of the ground and tried to take me as a hostage, but Mr. Fujimoto pulled me out of the way and Exorcised it in seconds! And it turns out the salt was really just sugar, so he didn't even plan to hurt the garden in the first place! He found the perfect solution where everything worked out perfectly, and I guess I was inspired!"

 _"_ _Perfect for everyone but the demon."_ Yukio almost said but held his tongue at the last second. Most demons weren't inherently hostile, but this one had taken a young woman's freedom and tried to use her as a human shield- it deserved everything it got. If it was let go, then there was a high chance it would repeat its actions and possibly even get someone killed one day. It was a mad dog to be put down after it had bitten one too many people.

(A part of him wondered how many people would one day say the same thing about Rin.)

Yukio nodded, "I see. Well, father does tend to have that effect on people, no matter what Rin says."

"Is that effect disgust? Because I'll agree to that."

Shiemi let out a little shriek and jumped at the sudden voice, while Yukio made for his weapon a moment before his common sense kicked in. Instead, he leveled a glare at the end of the table where Rin stood, peering at them with a critical and clearly judging eye. Very slowly, a smirk pulled at the corner of his mouth.

"So, how goes the date?"

Shiemi's face was tomato red in a matter of seconds and Yukio cursed himself as he felt his own face grow a bit warm. Rin's smirk was so shit-eating that Yukio very nearly punched him, and the urge only skyrocketed when Shiemi whimpered and tried to hide in her hands as Bon and the others ran over.

Yukio breathed in deeply, calmed himself, and slowly stood, "Rin, what are you doing over here? I thought you were working on the paper."

"Tried, failed, bored now."

Bon's angry shout from across the lawn turned plenty of heads their way, "Bullshit, you were just a jackass and left!"

Yukio closed his eyes, breathed in deeply, and tried to calm himself. It didn't work as well this time, certainly not helped by Bon storming over and looking ready to punch Rin through a wall. At least Shiemi looked only slightly flustered, probably from the liberal amount of swears and slurs being thrown around. He took her hand and started to guide her away, "Come on, Shiemi. We clearly won't get any work done out here, and we still have plenty to do."

Shima, having finally caught up, grinned cheekily at them and their connected hands, "Ooh, trying to get some alone time, are you?"

And because Rin was somehow eerily always aware of anything and everything to do with Yukio, he stopped mid-swear and glared at the pink-haired boy from atop his perch. At some point, he had ended up crouched on a table, clearly ready to literally pounce on Bon. "Hey, only I get to tease Yukio! That's my right!"

"The brother-complex sure is strong in this one…"

"What did you just say, cherry-boy?"

"I'll have you know that I have made _many_ beautiful women happy!"

To the side, Bon, suddenly ignored, watched as Rin and Shima argued and Yukio discretely led Shiemi away from the chaos. Several other students had abandoned their own work to partially surround their group, watching them as if they were strange animals. And really, compared to these rich brats, they probably were considering the way Rin abruptly tackled Shima to the ground, "…We're not going to get anything done without Yukio here to keep them under control, are we?"

Konekomaru huffed, plucking abandoned papers from the ground, "You're just now figuring this out?" Maybe he and Bon could form their own group, they didn't need Yukio that badly, did they?

* * *

"They're all idiots." Izumo stated, watching the chaos from a safe distance, lest she catch the stupid that seemed to become an absolute pandemic whenever Rin was around. She and Paku had finished plotting the general ideas they wanted in their paper and had decided that a little fresh air and a snack was a good idea. Honestly, she was quite happy with the topic: an extensive look into the entwined history of arias and summoning, and how the two had split from the same common study. It was a complicated but interesting topic, and she was confident that, if anything, they would struggle to stay under the twenty-page maximum.

So, of course, her good mood had to be ruined by seeing her fellow classmates make fools of themselves in full-view of twenty-some normal students. At least Yukio had the common sense to leave, even if he decided to drag that dead-weight Shiemi with him.

Izumo watched as Rin choked Shima with a rather brutal headlock, only to be dragged off by the school's security a few seconds later. For some reason, Konekomaru decided to try and defend Rin's utterly idiotic behavior, clearly talking down the officers even if she couldn't hear the words.

"Absolute idiots." She grumbled.

"Maybe," Paku said with a tiny laugh and Izumo nodded. At least her friend had some common sense, "but they all look like they're becoming good friends, right?"

Security had somehow been convinced to leave, and, Izumo witnessed what had to be a rare sight: Rin obviously embarrassed and, if she was reading the other's smug faces right, _thanking them_ for not letting him be rather rightfully dragged off and locked up like the borderline lunatic he was. She might have considered it progress if Bon didn't say something that immediately sparked another round of arguing.

It was disgusting to watch them squabble like children and get worked up over such petty problems. Yes, it had to be disgust that twisted her insides as she watched them bicker, argue, and yet for some reason, continue to willingly interact.

"How in the world do they look like friends to you?"

* * *

 **This chapter doesn't at all accomplish what I set out for it, but I just kind of needed to push past this 'hump'. I couldn't ignore things like this anyway, as bonding is incredibly important for when the thing that everyone is waiting to happen, happens.**

 **On a side note, I've broken 50k views, which is, well kind of insane when you think about how modestly sized the Blue Exorcist fandom is. Hopefully this story will continue long enough to double that.**


	29. Between Now and Tomorrow

Chapter 28: Between Now and Tomorrow

 **I'm thankful that this fic is finally getting somewhere.**

* * *

Shiemi sniffled from her position on the floor, feeling tears well up as Paku gave her a shy wave before she continued after Izumo...Leaving Shiemi all alone once more. She tried to smother the crushing feeling rising up in her heart, but it was hard to when her ankle throbbed like an angry reminder of her complete failure as a person. She enjoyed being around the guys in her class, but they were so rowdy that she felt overwhelmed and smothered by just how bright and loud they could be. Only Yukio seemed to really notice her, and that was because he had promised to tutor her.

All she wanted was to make a single friend and stop taking up so much of Yukio's time. She would have thought Izumo and Paku would be easy to get along with since they were all girls, but instead she made a complete fool of herself.

" _So lame."_

Shiemi really had to agree.

The blonde stopped, inhaled, and then exhaled. She couldn't keep crying over every little thing, she had to be strong! Even if it was hard, even if it was embarrassing, she had to keep trying!

Shiemi stood and immediately fell with a yelp.

And apparently being strong also meant limping herself home on a hurt ankle. She had absolutely no idea where the nurse's office might be in the school's overly long hallways, so it would be faster to head home and treat herself. Or at least that's what she told herself as the limped down the hallway, using the wall as support.

"What's wrong with you?"

Shiemi jumped at the sudden voice, and very nearly fell again. She would have if a hand hadn't grabbed her shoulder and hoisted her back to her feet as if she weighed nothing. Nervously, Shiemi looked back to see Rin's scowling face staring intently at her ankle. Suddenly something warm brushed where she was lightly holding her foot, and she yipped.

At her feet the demon cat she recognized as Rin's familiar meowed loudly and rubbed against her ankle again. Shiemi winced.

Rin huffed and casually nudged the cat away with his foot as if it wasn't a powerful demon, "I can see that she hurt herself, so stop making a racket, Kuro."

Shiemi tugged at the arm still in Rin's firm hold. He wasn't hurting her despite the casual strength she'd seen from him, but it still made her feel a bit trapped all the same, "I'm fine, I'll head home!"

"On that?" Rin frowned even harder, somehow. He looked so much like a scolding parent that Shiemi ducked her gaze away from him, "No, Yukio would be mad if I let you do that to yourself. Come here."

"What are you-! R-Rin!"

Shiemi very quickly realized that taking her eyes off Rin was a terrible, horrible, very bad idea. Without really knowing why or how, she was very suddenly in his arms like…like…like-

While the girl's brain stuttered and struggled to process what just happened, Rin took the opportunity to start walking, Kuro chirping happily at his heels, "What, I can't have you walking! And this way you can't run away."

It took much longer than it should have, but Shiemi finally realized exactly what was happening. Rin was walking around holding her like a…like a b-b-b-

Shiemi stopped her traitorous mind from finishing that cursed thought. She couldn't stop Rin from carrying her if he really wanted to, but that didn't mean she had to like it! So she buried her burning face in her hands, listing off all the correct plant names Yukio had taught her before her mind could try and betray her with terrible thoughts again.

So, of course, she didn't see the understanding pass over Rin's face, or the look of shame that he didn't quite manage to suppress. It only lasted for a moment before something dawned on the teen and he smirked.

Shiemi nearly screamed when she was moved _again_ , and suddenly she found herself slung over Rin's shoulder. Like a sack of fertilizer. She wasn't quite sure what to think, and instead settled for the only thing she could reasonably do right now:

"Rin!"

Rin cackled.

* * *

Yukio thought he was going to have a quiet day to himself, for once. Rin had left to do something-or-other with Kuro, Bon had declared that he would handle his friends on his own for once, and he had finally gotten a chance to see Shiro for the first time in weeks. It had been brief and unplanned visit mostly consisting of his father presenting him with the completed paperwork for Kuro to remain Rin's familiar indefinitely and to replace the temporary form he had been given before. It was something that had long been finalized and everyone who needed to know had been informed already, but having an official document on hand in case someone pressed the issue was useful. Since Kuro wasn't a summon, he was far more dangerous if he ever went rogue and typically considered too dangerous for a typical Exwire, much less a Page. But apparently it was easy for Mephisto to have those regulations ignored entirely.

Really, it could have been emailed to Yukio, but it was clear that Shiro had used it as an excuse to visit a "prodigy Tamer".

They had shared a laugh over that. The idea of Rin being considered a prodigy-anything was funny, even if the teen probably could be considered just as smart as Yukio, if he actually applied himself. Shiro hadn't been able to stay long enough for Rin to return, sadly, but it had been nice to talk for even a brief moment.

" _How is that brat doing, Yukio? He's not getting into too much trouble, right?"_

Yukio frowned, remembering how strained his father had seemed. It was obvious he wasn't getting enough sleep, and stress seemed to roll off him in waves. Yukio had asked, and even he wasn't supposed to know whatever had happened, it was easy enough to convince his father to at least tell him a little bit. He already knew that there was a war taking place for the throne of Gehenna (a war that Rin was going to eventually be used in, like a pawn, like a puppet-!) even if it hadn't fully broken out, so what was one more secret? Besides, he should know if only to keep Rin in line, right?

" _But that's the problem: Mephisto was so sure that Iblis would have made a move after Lucifer refused to take Gehenna. He hasn't made a move, but he's too ambitious to have given up. He's planning something, something big, and all we can do is prepare ourselves. All we do is prepare for an attack that hasn't happened for years now, and all the while demon activity keeps rising and keeps draining our resources."_

Yukio had wondered if Iblis had decided to wage a war of attrition, but Shiro had reassured him that Mephisto was sure that that wasn't Iblis' style. He, lacking the flames of Satan despite being a fire demon, had too many things to prove and too big of an ego to not take center stage- at least, according to Mephisto.

Samael, another arrogant demon who had already been wrong once before about Iblis, Yukio privately noted. And he wasn't exactly-

The door to the dorm was kicked open with a loud enough _bang_ that the walls shook. Yukio took a deep breath, steeled himself, and hoped that the door hadn't been broken by his careless brother.

"Rin, how many times do I have to…tell you…"

As expected, Rin stood tall in the doorway, looking almost proud of the rather pitiful creak the hinges of the door made as it closed with a worrying stutter. And over his shoulder was Shiemi, who was doing her absolute best to curl into a tiny ball despite her position. She whimpered a bit at the sound of his voice.

"What have you done?"

"She twisted her ankle," Rin stated as if that excused everything he had done, and strutted over to the table Yukio was using, "So you should fix her up," Rin set Shiemi on the table, effortlessly manhandling her and sitting her on the edge like a particularly red-faced doll and pointed sharply at her, "Help her."

"Just because I patch you up from your stupidity doesn't mean that I'm an actual doctor yet, Rin." Yukio sighed, but he was already by Shiemi's side.

The girl hadn't moved her hands from where they covered her face the entire time Rin had maneuvered her, probably hoping that he would get bored and wander off. While Rin's attention span wasn't _quite_ that bad (school notwithstanding) at least she didn't seem hurt, just embarrassed beyond belief at how she had been carried, and probably seen by the entire school. She sat there, stiff and probably a little traumatized by Rin being…well, Rin. Which meant being utterly bull-headed and overwhelmingly insistent with whatever he had decided to do. When he rested a hand on her shoulder, she finally peered up at him shyly through her fingers.

Rin huffed, "Well, are you going to help her? Or do I have to _carry_ her all the way to the nurse's office?"

Shiemi squeaked and scooted away from Rin as best as she could, "I-I told you that I'll be fine! You didn't have to bother Yukio for me!"

"Oh, I don't think it's a bother for him, right?"

Yukio felt annoyance bubble up and stepped between the two of them, "I already told you, I'm not your personal doctor, Rin. And I think that you've done enough for today, so please leave."

Rin gave Yukio a look that, for some reason, made him feel like an idiot. Like he had missed something glaringly obvious, but he had no idea what, and his brother's next words were too cryptic to make the look make sense, "That's not what I was talking about, but ok…"

"Leave."

Rin stared at him with one of his unnervingly unreadable gazes. Yukio could never get used to the feeling of being studied so intensely by his usually flighty brother, but he had learned to stand his ground. And so he stood tall enough to not appear weak, but loose enough to not seem stiff and fake. Rin's too-blue eyes glanced back and forth between him and Shiemi a couple of times before a rather self-satisfied smirk pulled his lips apart.

"Ok!"

And Rin winked at Yukio before sauntering out, in such a pleasant mood that Yukio felt almost cheated. Rin didn't like following orders, even Yukio's, and seemed to enjoy being difficult just for the sake of it. He had expected for there to be a lot more resistance, but instead, he seemed satisfied and left.

He shook his head. He really didn't understand his brother sometimes.

"I am so sorry about my brother, Shiemi." Yukio called out as he grabbed his medical kit (always on hand, just in case), "Usually he isn't this bad, but when he gets an idea in his head, there's not much I or anyone else can do to stop him."

Shiemi shook her head, still flustered but looking better already, "It's fine, it's fine! I wasn't scared." Yukio raised a brow and she flushed, ducking her head to mumble, "Well, I wasn't _that_ scared…I didn't think he was ever going to hurt me, but it's a bit frightening to get carried around like that…"

"Don't worry, I'll be sure to have a long talk with Rin about little things like personal boundaries." Not that there was a high chance that that would change anything, but he had to at least try to do something before his brother unintentionally got a sexual harassment charge filed against him or something equally ridiculous and headache-inducing, "But he was right- you shouldn't walk on this much for the next couple of days if you want it to recover in time for the training camp. What caused this anyway?"

Shiemi refused to meet his gaze, looking anywhere but him, "I…I tripped! I'm just so clumsy, you see…"

"Shiemi, you're a really bad liar."

"But I really did trip!" The blonde insisted, "I was just trying to catch up to Izumo...and…"

Ah, now he could start piecing together a picture, "And she just left you there when you fell? That's pretty harsh."

"I mean…" Shiemi fumbled, picking at the hem of her kimono.

"Though really I'm more shocked that Paku would just leave you. She _was_ with Izumo, right?"

"Yes, but how did you know?"

"Just a guess, since she and Izumo stick together a lot." 'Like a lost dog' Yukio barely resisted saying. No, Shiemi didn't need to know the dark and judgmental things he thought about some of his classmates, "I guess I'm just disappointed that she didn't help you…Is that too tight?"

"No…"

There was a slight waver to her voice, and she looked nervous.

"Is something wrong, Shiemi?"

She shook her head, smile forced, "No, my ankle just hurts a bit! I need to go home and rest, right?"

Yukio knew when someone was hiding what they were feeling, and Shiemi was far worse at it than Rin had ever been, "Yes, yes you should…If something is bothering you, you can tell me, you know. We're friends, right?"

"Ah…" Suddenly Shiemi was staring at him, garden-green eyes huge with obvious shock. He wasn't sure what he had said that was so strange until the next words slipped past the blonde girl's lips, barely a whisper, "F-Friends…?"

"Are we not …?" Had he misread their relationship? She seemed like a nice girl, so surely she would want friends and not insist on lone-wolfing it like Rin did.

"No! No, it's just…" Shiemi blushed and played with the hem of her sleeve, and mumbled, almost silently, "I've just…never had a friend before…"

* * *

"Hey, asshole!"

Satan rolled his eyes at the familiar voice. And right when he was in a good mood, too.

"What is it, chickenshit?"

"At least Bon finally has some good company…"

Ryuji glared at him, pissed off as always, and stormed right over to him, leaving his lackeys to trail behind. Konekomaru looked exasperated while Renzo just looked amused. Hell, the pink-haired bastard gave him a thumbs-up for some idiotic reason that probably only made sense to himself.

Satan's view was obscured as Ryuji decided to invade his personal space. For some reason the boy hadn't realized that his superior height wasn't the least bit intimidating to Satan when really it just made it easier for Satan to sucker punch his vulnerable stomach. Or take a pot-shot at his crotch and end whatever fight might start in seconds. There was no such thing as a fair fight, after all.

Ryuji, ignorant to Satan's casual thoughts of bodily harm, growled at him, "I want to know exactly what the hell you think you're doing with Shiemi? Everyone's been talking about you carrying some blonde girl in a kimono around like you own her, so I want to know what the hell you think you're doing! And what did you do with her anyway!"

"She twisted her ankle, so I took her to Yukio so he could help her," And maybe things between them would…progress. Or they wouldn't, and Satan would have to give up on pairing the two of them together. They made a cute couple, she was nice, and, most importantly, Shiemi wouldn't even think of using Yukio. So, she was, by definition, perfect in his books. But love was tricky, destructive if done poorly, and it took time.

Yukio, thankfully, didn't seem prone to throwing himself at the first pretty face that was even slightly nice to him.

Konekomaru spoke up, skeptical, "Shouldn't you have taken her to the nurse instead?"

Satan missed when the kid had been outright terrified of him, "Maybe, if I was a simpleton like you. But Yukio is perfectly capable of tending to Shiemi all by himself," And they needed time alone to talk, hopefully about their feelings, "Don't forget that he does the best on the Doctor tests than any of you ever will. That includes even you, bonbon."

Ryuji made an angry…something. Satan was pretty sure it was supposed to be an oh-so intimidating growl, but it came off more as 'choking-cat' than anything else. He probably had some 'clever' retort ready, but Satan was acutely aware of the eyes on him.

His hand disappeared for a second before the glint of a switchblade caught the light. He heard the trio next to him gasp and shout at the sight of the meager weapon like he had just pulled a six-foot longsword out his ass, but Satan ignored them, "Besides, we have a bigger problem to worry about."

"What!"

"Whoa, where did you get a knife-?"

"The hell are you doing!"

Konekomaru screamed as the knife missed his ear by only a couple of inches. The blade flew between him and Renzo with unerring accuracy and, behind them, someone yelped as the blade scrapped a shoulder.

They whirled around just in time to see a black-haired boy run away, nearly tripping over his feet as he fled.

Satan saw familiar blue-green eyes and huffed, "I hate spies."

Ryuji trembled with obvious rage, and Satan had just enough time to sigh before the taller teen exploded and started screaming, "What the hell was that!? Did you just really throw a knife at a student?"

"He's been spying on me this entire year. I think he got off pretty easily."

Konekomaru frowned, shaking a bit at the near-miss but more intrigued with the strange turn of events, "Rin, you have a…a stalker? Shouldn't you report this to the principle?"

Satan barked out a humorless laugh. If only this kid knew what Samael could be like- he would probably find the entire thing amusing and Satan was set on avoiding him as much as possible. Just because he hadn't recognized who Satan was at their first meeting didn't mean he wouldn't catch on, however ridiculous it seemed.

Renzo whistled, long and low, "Wow, a spy? Pretty crazy that anyone would be interested in you. Guess you're pretty popular, huh?"

"Next time I catch him spying on me like a fucking creep, I'm going to kick his shit in."

Renzo laughed nervously.

* * *

" _Were they immortal?"_

" _That's a hard question to answer, but, in the end, they really weren't. They were born, they lived, and they could die, but only when they were ready to. Nothing could kill them except themselves, when they finally had their fill of life."_

" _So, does that mean…?"_

* * *

Lucifer stared in the mirror. Acid green eyes watched him in turn, as impassive as ever. Idly he rubbed at the long-healed needle wounds on his neck, checking himself for any defects. Soft skin that didn't flake away, healthy blond hair that didn't fall out in clumps, even the cuticles on his nails grew without flaw. It had been months now, but it still felt strange to no longer feel the pain of existence. A primal part of him missed the affirmation of his struggle, but it would be foolish to allow himself to fall into decay once again.

Without a doubt, Gedouin had outdone himself. It wasn't perfected yet, but Lucifer had little doubt that the man would find a way to make the effects of his Alpha Elixir permanent soon enough. Lucifer had never intended to use the Elixir, but Iblis had been…difficult to control. Even when their goals didn't overlap, Iblis was still needlessly reckless and head-strong and refused to wait until Lucifer's plans had completed before enacting his childish coup. Honestly, he had been waiting thousands of years, what were a few more to beings like them?

Lucifer dressed himself slowly, watching as his skin was hidden by fabric once more. Once, even the brush of the finest silks sent fire dancing across his broken and chipped body, but now it was a pleasant feeling. Pleasant, but only temporary like everything else was.

Like even father had eventually been.

Yes, Iblis and his other brothers could have this world and do with it whatever they pleased. Lucifer had no love for flowers that would one day wilt, no need for a family that would soon kill itself now that father was no longer here to keep them in line. He may finally have a body, he may finally have the freedom he always desired, but none of it mattered in the end. Nothing did, and that was something he just couldn't stand.

No, it was his duty to pick up the mantle that his father had forgotten over the eons. Maybe he had grown weary and made the mistake of resting, maybe he really had lost something to cursed eldritch creatures he had hunted, or maybe he simply lost hope. The cause did not matter, the reason did not matter, only the results mattered. Only the future mattered.

And so, Lucifer would move on, move forward, and discard finality.

* * *

" **Don't expect a huge overarching plot, nor for this story to actually go anywhere significant."**

 **A little less than 2 years later (has it really been that long? Wow) and I think I can officially eat my words. I hope everyone is ok with** _ **heavy**_ **divergence from canon, because that's what you're going to get soon. I can't say exactly how things are going to change since I clearly have no control over this story anymore.**


	30. Sharper

Chapter 29: Sharper

 **Blue Exorcist doesn't go super in-depth with some of its systems, so I have to fill in the gaps with my own headcanons in order to make things work a bit better.**

* * *

The circle sparked to life, malicious energy built and bubbled from the center. It bulged, and, from the depths, clawed hands reached out. The deformed human corps burst free, a low moan pulled from its distorted face as the smell of sulfur filled the room.

Satan glared at the Naberius with disinterest and bared his teeth in a challenge when it looked at him. By his feet, Kuro hissed.

"It stinks," Satan explained when Igor tried to cow his behavior with what the human probably thought was a threatening glare. Honestly, Satan wasn't even somewhat impressed by a lowly Naberius, and a fairly weak one at that. It was likely that the teacher had selected a weak one on purpose lest he scare the children, but that only made it worse. Trying to force your will over another demon's was dangerous and potentially deadly, but Igor really wasn't emphasizing that enough.

"Now everyone, put a drop of your blood on the paper with the magic circle I gave you earlier. Except for you, Mr. Okumura- you already have a familiar, and a contract one at that. You hardly need more."

"It's not like summons are that useful anyway. You break the circle…" Satan drawled, pointing at the chalk with his foot, "And 'poof'! Your support is gone."

"That may be true, but summons can be canceled quickly." Igor countered, "Everyone should remember that if a summoned familiar is out of control, you can destroy the circle to save yourself."

It was stupid to summon something you weren't sure you could put down, but then again, the Exorcists also thought that working with Samael was a good idea. Idiots, and they deserved everything they would inevitably get, "That just happens if you're weak. Don't be weak."

Yukio coughed, waving his blood-smeared circle to catch everyone's attention, "Rin, I think that's enough. It looks like I don't have the talent."

Satan could practically taste the lingering power in the air, so that was a blatant lie. But then again, Yukio had never liked overtly standing out, and Satan couldn't disapprove of him have a potential ace no one else knew about. A quick glance showed that not a single one of Ryuji's group had managed to summon anything, though Satan could swear he felt a touch of power receding from them. They had clumped up, so he couldn't tell who it was, but he was sure that one of them held the ability, they just hadn't properly reached out.

Odd, but then again, they all seemed like idiots. None of them even looked aware that a demon had been ready to answer their call.

"-Fulfill my prayers!"

Satan's thoughts were cut off at the absolute surge of power near him. It quickly peaked and burst free, forming not one, but two Byakkos that obediently sat by Izumo's feet. Satan was very suddenly forced to reevaluate his opinion of the twin-tailed girl: she might be a bitch, but it took no small amount of strength to summon two decently powerful demons with such complete control. There wasn't a hint of dissatisfaction at their summoning despite the pride they practically radiated, and the girl seemed perfectly at ease in their presence.

Paku gaped at the marked fox spirits, a sentiment shared by everyone present, "That was amazing, Izumo! I can't do this stuff at all…"

Izumo smirked, clearly satisfied at the praise the entire class was heaping upon her, "It's just natural. I'm descended from a proper shrine maiden, you know!"

Well, that at least explained how familiar the foxes were being with her, happily circling her. Beside him, Kuro meowed in agitation at being ignored, "Rin, I'm a lot better than some foxes!" Kuro whined, pawing at his leg, "I can get big and I'm a lot stronger and I won't trick or betray you or anything like that!"  
Izumo sneered at him when Kuro's mewing became incessant, "Having trouble controlling your familiar, Rin?"

"Hardly. He just doesn't like it when I pay attention to lesser demons," Satan huffed, giving in and picking up the Cat Sídhe before the demon started climbing his leg or something equally undignified, "Besides, if you think I'd be jealous of you, you're insane. Foxes are deceptive and crafty and will eat your heart the moment you give them a chance, but Cat Sídhes are pretty damn loyal. Don't slip up, ok?" He grinned, voice filled with light cheer.

Izumo flinched as if he had slapped her.

Satan was pretty sure his sneer wasn't that frightening, but sometimes he underestimated himself.

Abruptly, Shiemi spoke up, "I want to try too!"

Satan watched the blonde summon, frowning at her half-assed chant. It was a lesser-known fact that the exact words didn't matter nearly as much as the intent to summon itself, but did she have to sound like she didn't have a care in the world? She was summoning a demon who would eat her soul the moment she showed any weakness, she should take this a little more seriously-!

A Greenman popped into existence with a blip of power so tiny, Satan almost missed it entirely.

Well, Satan decided as he watched the Greenman (so tiny, it had to be young) cling to Shiemi, he didn't have to worry about the girl getting devoured by her summon anytime soon. The Greenman was too weak to hurt her and could only endanger her if she recklessly fed it her power. He was also pretty sure it was imprinting on her.  
Kuro meowed in his arms, tails twitching, _"It looks like a mouse! Can I-?"_

Satan rolled his eyes and dropped the Cat Sídhe.

Cats were supposed to land on their feet, so Satan thought he could be forgiven for what happened next. Kuro landed on his back with all the grace of a wet rag and rolled…right over the summoning circle's lines. Chalk was obviously a terrible thing to use for finicky runes and spell circles if it came off so easily, Satan decided. It really wasn't his fault that they used such a shitty thing to make their lines- if they cared so much then maybe they should use paint or a marker or something a little hardier!

Igor stared at him hard as the Naberius fell back into Gehenna with a low groan, looking like he was seriously considering beating one of his students with his oversized chalk-drawing-thing that was still clipped to his hip.

Satan looked down at the smudged circle and the blob of black now sitting in the middle of the carefully crafted lines. Kuro paused, mid-motion to clean himself, letting his hatred for the chalk's taste known, though the rest of the class probably only heard a pitiful whine.

Satan nudged the demon with his foot, "Hey, look what you did."

 _"You dropped me!"_

Ryuji deadpanned, "This is clearly your fault, idiot."

"I don't want to hear it from someone who couldn't even get Coal Tar to listen to him, Bon-bon!" Satan shot back, doing a rather admirable job of not punching that smug look off Ryuji's face, in his personal opinion, "And cats are supposed to land on their feet, damn it! How is it my fault that the shitty priest gave me a defective cat, huh?"  
Izumo sneered, looking one step away from laughing in his face, though her Byakkos were very doing exactly that, muffled as it was. It was a sound only slightly more annoying than her face. The plum-haired girl was blissfully oblivious of Satan plotting ways to skin her summons and she slyly looked over to Yukio, "Your brother is an idiot if he thinks that's going to work."

It was less the words themselves and her holier-than-thou tone that set Satan off once again. She must think that she was so special just because she had a little talent at summoning. But that was the only thing she was even passable at, and Byakkos weren't even overwhelmingly strong- even the weakest of his children could easily crush them and devour their spirits, so nothing would be left to return. Hell, he could probably take them as he was now, and he wouldn't even have to play dirty and go for the paper! "Wanna go, twin tail bitch? I'm damn sure my familiar can take both of yours."

With the chalk already ruined, Igor had no qualms with stepping across the circle to stand between Izumo and Satan, "That's enough, children. Remember what you've learned today and don't hesitate to tear or otherwise ruin your summoning circle if you ever feel that you're in any danger. Rin Okumura, you'll be staying behind to finish cleaning the summoning circle." Not once did his eye leave the short boy.

Satan just looked offended, "I'm not cleaning your shitty and overcomplicated art project up."

"Mr. Okumura, I am your teacher and you will listen to me if you don't want punishment," The one-eyed man stated, no, demanded that his student listened to him, "That's an order, not a request, and you'll listen."

"'Punishment'…how delightfully vague and not threatening at all. Unless you have a reputation, it pays to be specific if you want me to be afraid of you," Satan drawled, idly picking at his nails as a way to disguise a movement to check his knives. He had never liked this teacher as something about him just rubbed him the wrong way, and he wasn't good enough at hiding his naked hatred for Satan to not have noticed by now, "What are you going to make me do, write lines, stay after class…what? And how the hell are you even going to make me do any of that anyway?"

If it came down to a fight, Satan was sure he could take down the oh-so-powerful Exorcist. Maybe it would be a nice lesson to the class that you couldn't rely on fancy tools all the time, or else you'd be helpless if you got surprised. And if the teacher got a nick on his face just deep enough to leave a scar, well, that was too bad, accidents did happen after all.

The room was tense, choking everyone present under the sheer intensity they couldn't properly understand. It was the feeling of static dancing on the skin, of coiled muscles and tension ready to be released. It would build, poked and prodded by Satan until it was as high as the sun, filling with burning feelings and boiling blood.  
It had been too long since he had really fought anything.

And, like a cool breeze that toppled a child's tower, Yukio stepped forward, hand raised, "If you won't do it, then I'll take responsibility for my brother's actions."

The word 'responsibility' sent an icy shard of fear straight to Satan's core. That was a…a very dangerous and slippery slope that Yukio couldn't possibly understand the implications of. Even just 'Rin Okumura' had done plenty of illegal things, including murder (that filth deserved it, how dare they be even a peripheral threat to Yukio, inexcusable, intolerable, howdareth _eyhurt_ -) and though he was sure no one could connect such things back to him, the demon was sure that the Exorcists had an entire file room dedicated to charges against Satan from the Blue Night alone.

Modern courts might have finally discarded the idea of passing the father's sin to their children, but religion had always lagged behind. They apparently still thought burning witches was acceptable (red, red, redr _edred_ \- Blue.), so he was pretty damn sure that they would dig up whatever archaic rules they could to crush his last hope, his last tie to Yuki, his very last reason to-

Satan shook his head so violently the room spun, squashing terrible thoughts before they could swell. No, he had the here and now, he had to stay 'awake' for now, "Yukio, you don't have to do that!"

Yukio frowned at him, obviously catching the sudden strain in his voice, "Yes, I do. Like it or not, I'll take responsibility for your selfishness." The younger boy might have said those words, but really, Satan could read him easily. There was obviously worry there.

Satan huffed, looking away until he could lock away his darkness again. In lieu of answering the unasked question, he shrugged, and worried his lip as he sorted out his chaotic thoughts. "…I just don't fin-"

Blood.

His mouth was filled with blood.

Satan covered his mouth quickly but just ended up smearing blood all over his hand. It wasn't much, but it still made an ugly sight.

"Rin, you're bleeding-!"

"-'m fine-fucking-!" Satan hissed, cutting off his swears as he did nothing but exacerbate the cut. Honestly, if anyone knew what was actually happening, he would be seen as an absolute idiot and his reputation would take years to recover. But they were ignorant, so instead the class looked at him, worried, as he seemed to be suddenly spitting blood to them.

"I'm leaving," Satan mumbled, barely suppressing the heat trying to combust his face. A few of them called out after him, but Satan pushed forward- he had to get away so he could sulk in peace.

Splitting his lip open on his own fangs, just what kind of demon was he!?

Well, the better question was exactly when he grew fangs.

Five minutes later saw Satan pulling his lips back, baring his teeth at the mirror. His reflection snarled back at him, his teeth just a bit sharper, a bit deadlier as they tapered into points. He frowned at the reflection, feeling his scalp for lumps, checking his ears for a point, and staring into his own eyes for any reflection of hellfire. He saw nothing, but his teeth were definitely just a bit sharper. Idly he ran a finger over the sharpest canines and could feel the edge ready to cut his skin if he pressed a tiny bit harder.  
They weren't fully developed, but Satan was pretty sure he hadn't had even these baby teeth just last night. At this rate, he would have a pretty impressive set by next week. As a test, Satan pulled his fire from his heart, and let a small flame dance on his finger. It comes easily, with only the faintest tug.

Well, that was probably a bad sign.

The bathroom door burst open, and Yukio stormed in. Satan crushed the ember in his hand, but words still fail him at the determined look on Yukio's face. Oh boy.

"Open."

"Err…"

"Your mouth, Rin. Open it now."

Satan forced a grin instead, and nearly swallowed his tongue when Yukio grabbed his jaw and forced it open. Satan holds himself as still as he can as Yukio carefully examined his teeth, prodding the noticeable pointed incisors enough that he's afraid his kid is going to cut himself. But Yukio is very nearly a professional Doctor as it is, and he's careful enough despite the rough treatment.

But the boy isn't happy with what he sees and he pulls away with a growl, "Damn it Rin, when were you going to tell me about this!"

"I just noticed them today. It was a slow enough process that I didn't realize they were there!" Lies, lies, but it'll be worse to say that they just grew overnight.

"I managed to convince the class that you bit your tongue, but what are we going to do about…" Yukio gestured vaguely at Satan's face, "about this?!"

Nothing, because there was no way to stop a failing seal this far in, "It's not a big deal, Yukio."

"Not a big deal? You're growing fangs Rin! Fangs that you just hurt yourself with!"

"Hey now, I wouldn't call this 'hurt'!" Severed limbs or sharp objects making friends with his ribcage was usually the bare minimum of injuries needed for Satan to think of himself as 'hurt', "I'm just not used to them yet. It's not like they're going to get long enough to rip through my jaw or some shit." Though, he had noticed some acute aches in very specific parts of his back recently that might cause some… 'growing pains' if things kept progressing. The damn seal was doing next to nothing now.

"And what if they do? What if they never stop growing and you end up ripping apart your own mouth? What then?" Yukio countered, nearly hysteric.

"That's not going to happen, and you know it! My teeth will just be a little sharper, so what?" Satan countered though the thought of the failing seal sobered him quickly. Yukio was afraid, had every right to be, and, to be completely honest, Satan was a bit afraid himself. The glass house he had lived in for a decade and a half was going to crumble very soon, and there wasn't a thing he could do to stop it.

So, all he could do was mitigate the damage, "Yukio, you had to know that this was going to happen, right?" The nod was hesitant, but still there, "But in the end, it doesn't matter because it's just my body. Even if I grow a tail and sprout horns and wings and start spitting fire, it'll still be me under all that shit. So, you'll still love me even then, right?"

Yukio refused to look at him still, shifting nervously and fiddling with a loose strand of his uniform. The stretching silence was crushing, every nanosecond without an answer threatening to break Satan. He couldn't breathe, he couldn't blink, he couldn't even properly continue existing until he knew, until Yukio said those words, until Yukio reaffirmed the faulty world he had built.

"'Love'…is a strong word to use some days…" Yukio started slowly, coy enough to widen Satan's eyes, "But yes, so long as you stay yourself, I'll still love you. And even if you somehow lost yourself, I'll drag you back kicking and screaming."

"And spitting fire," Satan added, glad his voice didn't betray the sob of relief he felt building in his chest. Choking him once more, but this time in a way that made him want to hug and squeeze Yukio breathless. But he would worry if he did that.

Yukio sighed, and they both politely ignored the way it shook just a bit, "You just want to be able to burn your homework at will, don't you?"

"And burn the shitty priest's eyebrows off! Do you know how long those things take to grow back? It'll be hilarious."

"As 'hilarious' as using mace on a Demon King…"

"I still have the bottle, for memories!"

Yukio rolled his eyes, and Satan could see the tension falling away from him with the motion, "Smile for me for a second…They don't look too noticeable at least, and I don't see any other changes in things like your eyes or ears."

"Why there?" Satan knew exactly how he was going to change, but Yukio?

"Mr. Pheles said to keep an eye on all of those spots and to notify him if we notice any changes. It could mean that the seal is getting especially weak," Yukio explained, examining a strand of his twin's hair. It really was turning blue.

Satan pulled away and made a face at Samael's stupid made-up name, "You aren't actually going to tell that creep, are you?"

"No, of course not." Yukio declared vehemently, "It might have been a few years, but I haven't forgotten what happened that day. He outright admitted that he wants you to act as a puppet ruler for him, and he needs you to be a demon for you do that, doesn't he? I wouldn't trust him to not somehow accelerate the decay of the seal instead of reinforcing it."

Satan couldn't help but grin at that. Well, there was one problem taken care of before it could even begin. Sadly, he was sure that Samael would figure things out on his own soon enough, but Satan would take every shred of faux normalcy he could get, "I didn't realize you had such a problem with authority, Yukio."

* * *

"I'd normally blame you for being a bad influence, but Mr. Pheles has all but said that we shouldn't trust him. We might all want to protect Assiah, but he's already hinted at some sacrifices I'm not willing to make."

"So, we both agree that we aren't telling him, right?" A nod. Good, now for the hard part, "So that means we can't tell Shiro either. Oh come on, don't give me that look! The moment something went wrong, he called Mephisto for help explaining everything to us! There's no way he wasn't planning for that day, which means that those two have to be pretty close for the supposed principle to come running over." Or Samael just wanted to avoid his duties and jumped at the chance to leave. Either way, Satan couldn't afford for the Paladin to be breathing down his back, or for the shitty priest to do something rash.

"I guess you're right…"

"I'm not saying that Shiro is bad like…Mephisto is, just that he's been tricked into trusting him. Shiro will always be a shitty priest, so of course, he probably asked another demon about what to do when it comes to me…" It actually made a lot of sense in hindsight. Shiro would have no one he could trust, but Samael would have enough overlapping interest in him that, if nothing else, he wouldn't try and kill the son(s) of Satan by default. He already helped with the sealing, so he was invested enough to not ruin his own plans.

Hopefully.

* * *

The demon crashed to the ground, its great and powerful bestial body crippled and twisted. Wings were shattered, its chest caved in, and its tail had been broken in several places. It was doomed, and yet the once great Manticore demon tried to crawl to its feet and escape.

It was much too slow, and a great meteor crashed into its head, powdering bone and turning brain to mush.

Amaimon stood slowly, shaking off the blood from his hands. He kicked the demon's crushed head, sighing as he realized it was already dead. He had hoped that with all the fuss the Exorcists were making, the demon might have been at least a little challenging, but…

Weak.

He looked up and could see all of the black-clad Exorcists shy away from his dull gaze. Well, all but one, but he didn't even bother to wear that stuffy-looking uniform, so he didn't count. He was a weird human, but Amaimon didn't completely hate him anymore. He only wanted to crush his skull a couple of times a week, instead of every single day.

Lewin Light waved, willfully oblivious to the disturbed look his comrades gave him. He supposed their shock at a Demon King's power was understandable- even he would have had some trouble with the Manticore, but the Earth King hadn't even needed to release his heart even with the disadvantage he had. It was only natural that humans would be scared of such power, but Lewin had long stopped being afraid of such trivial and unchangeable things, "Come on, Amaimon, it's time to head back. These guys will handle the small fry for us."

"Small fry" being a slew of golems of varying sizes and shapes that a magically-inclined Echidna had created. There had been other, much more dangerous demons, but…Lewin glanced at the smear that had once been said Echidna.

Demon Kings were something else. And maybe he really had gone mad, but Lewin really wanted to properly tame Amaimon. It was something that went against common sense, but so was shortening chats and fatal verses.

Amaimon frowned at the strange human. Even if he had only started listening to Lewin because Mephisto had told him to, he could admit that the human wasn't that bad. He wasn't properly afraid of him, wasn't properly respectful enough, but he also liked Amaimon for what he was: a powerful demon. Fascination wasn't proper awe, but it made the human tolerable.

And in the end, Amaimon still held the power, and would wield it as he saw fit, "But I want to mess around a bit more. I'm bored," The Earth King drawled, making sure the stretch out the word just enough. He didn't actually want to fight some weak golems, but there was plenty of other fun to be had, "You keep saying you need me for the war, but I haven't gotten to fight anything fun yet. I really wanna kill Iblis now that father is gone."

Amaimon's voice hadn't fluctuated much from its usual bored tone, but the lower Exorcists around Lewin still flinched at the obvious threat. The Demon King hadn't always been as willing to play nice. Lewin just nodded, cheer never fading, "Yes, yes, we're all frustrated waiting for Iblis to finally kick things off. But the ice cream store closes soon, so you can either keep playing or get a treat. You decide, of course!"

Amaimon didn't smile, but he still internally preened that he had trained his human so well. Now he could pretend to be ready to cause trouble, and Lewin would rush for a way to keep him calm, "...I want a milkshake."

"It is hot out, isn't it? Well, follow me."

Lewin grinned. Amaimon really did think he was clever and subtle, proud that he had once again 'tricked' the great Lewin Light. Well, it was certainly better than dealing with the naked threats and demands, and he wasn't going to complain when Mephisto had dumped effectively infinite money in his lap to keep his little brother under control.  
Besides, the best way to get someone to do something you wanted was to convince them that it was their idea in the first place. And if he was seen as a source to easy treats and fun (fights), then all the better.

* * *

Amaimon sipped on the milkshake, idly watching the weak humans walk past the store window. It wasn't one of the nicer ones with chocolate painted on the sides and a slice of cake on top since apparently Lewin didn't have enough money on him, but it would do. For now. He was half tempted to rob a couple of the passing humans for the extra money, but that would have led to a fight in a very public place. And while he was pretty sure he could take out Lewin if he was quick enough, Mephisto wouldn't be happy. And he would be stuck with a stuck-up Exorcist who probably thought demons were nothing but tools and expected his complete obedience and a proper contract.  
So, he would settle. For now.

"Hey." Amaimon started, the thoughts of bloody conflict with Lewin reminding him to a certain day not too long ago when he had misbehaved. He had thought about killing the human for yanking him around that day, but decided it wasn't worth it, "When do I get to meet my littlest brother. For real, this time. Mephisto seems to think he's interesting but you dragged me away before I could talk to him."

"Ah, well it's rude to interrupt class you know!" Lewin laughed, though in his head he was ready to pull forth a demon or six at a moment's notice. This was always a tricky topic considering the, frankly, nightmarish logistics, "But not everyone can know he's your brother just yet, so you can't talk to him yet. Besides, he isn't even a proper demon yet, so if you try to play with him, you just might break him."

"Humans are weak." Amaimon nodded as if he had just stated a fact of the universe.

"Yes, well, once he awakens, I'm sure Mephisto will arrange something for you." Lewin deflected. It was probably for the best to shove responsibility for this onto someone else, and who better than another demon?

"Why can't he just wake up then? This is taking too long."

Lewin sighed, not sure how to explain everything, "Well, this is an important step in his life that he has to do willingly or he might get devoured by his own fire, at least according to Mephisto...and he's not very well behaved either, and…I'll just shorten the rest and skip to the end: The Grigori don't want another son of Satan running around if he won't be useful."  
It was a whole lot more complicated than that, but Lewin had quickly learned that Amaimon didn't like complicated things.

The Earth King stared at the scruffy man for a long moment, gaze as unnervingly unblinking as ever. But he seemed to understand at least one of the excuses Lewin had rapid-fired in hopes that one would stick, and slumped, "I hope the war happens soon then."

"The sooner it happens, the sooner we can be done with it, yes!" Lewin agreed. Honestly, everyone was so tense and scattered as they dealt with upstart demons and increasing reports. He hadn't seen Arthur in months and was pretty sure the man was stuck culling weak demons before they could get out of hand.  
Lewin watched the Demon King play with his straw, drink long finished. Others might have dismissed him, as his lower intelligence was well-known now. But, just because he wasn't a genius like Mephisto didn't mean he wasn't a threat in his own, erratic way. And He could see the clear spark of intelligence, of cunning and plotting as the demon stared with an expression anyone else could call dull at his empty glass.  
"Oh and, Amaimon?"

"Hmm?"

"You aren't going to do anything, ah, rash to try and make your little brother wake up sooner, are you?" Lewin asked, light as the Sylphs he liked the summon, and just as sharp as their wind, "Because I like you, and I don't want to have to be mad at you, ok?"  
Disobedient demons needed to be exorcized, lest they get cocky.

Amaimon looked at him without moving, eyes sliding the rake of a claw over the Arc Knight's form. It was obvious how he was judging and sizing up Lewin, like a cat with prey.  
How anyone thought Amaimon a hopeless idiot, Lewin would never know. He might not be a thinker, he might get confused by the complexities of the world, but he knew exactly how far up the food chain he was.  
"Ah, no. Big brother would be mad at me. Iblis is an idiot, so he'll do something stupid soon anyway."

"Good, good. I wouldn't want us to have a spat after we've been getting along so well!"

"Humans break easily, so that would be bad."


	31. The First Act

Chapter 30: The First Act

 **Finally, this fic is slowly but surely peeling away from canon as the long-term effects of both Satan and Yukio being present in the class start to take hold. As for those who are worried about how things are kind of dragging out, that's because once the real plot kicks in, it isn't stopping for** _ **anything**_ **for a long time.**

 **I also went ahead and cut a lot from this chapter since I do think things were moving too slowly. A lot of stuff is now implied, but the conversations weren't overly riveting.**

 **Edit: For anyone getting a double update, sorry. There were issues with the chapter posting a reviewer pointed out, and I at least couldn't see my own chapter on my end, so I just deleated and reposted.**

* * *

Satan knew Yukio had started to spend time with Shiemi beyond just their study sessions. Apparently, they were now friends, and would hopefully become something more given enough time. He wouldn't force them together since love was tricky and could be nothing more than a mirage if done poorly, but that didn't mean he wouldn't give them little…nudges. A comment here, a shift in seating there, a little bit if misdirection so they just happened to be at the library at the same time…

Innocent tricks had been how he and Yuki had gotten together in the first place, so he supposed it wouldn't hurt so long as he didn't, say, lock them in a closet until they sorted things out.

Yet. He was a demon and had only so much patience, and Yukio didn't even have to overcome the whole 'murdering your teammates and being literally Satan' issue he had had. Not that Yuri had always had the noblest of intentions herself, but that's just what made them even slightly compatible. Either way, things were going along smoothly.

So, of course, that Izumo bitch had to get in the way.

He wasn't sure what had happened when he had rushed out of the summoning class the other day, but somehow-

Izumo carelessly waved a stack of papers under the blonde girl's nose, "Shiemi, I forgot to deliver this, so can you do it for me?"

"Sure!"

There wasn't even a pause to consider why _she_ should be the one to do it. Izumo had stopped even bothering giving excuses when it became clear that Shiemi would do anything to earn her approval, wanting desperately to be useful.

"Shiemi, if you don't want to do something, you don't have to."

"It's fine, I want to help out my friends just like you do, Yukio!"

"That's…"

-somehow, Shiemi thought that she had to earn the twin-tailed brat's approval. Satan was of the firm opinion that friendship wasn't something to be given out nearly as freely or easily as humans tended to (it had ended with more than a few knives in his back) but it was painfully obvious that she was just being used.

He nudged Yukio's shoulder, "Hey, you need to talk to her about not being the bitch's bitch."

"I will." Yukio affirmed, and then, after a long pause, added almost as an afterthought, "And don't be so crude."

"Crude, not wrong."

"Hmm."

The fact that Yukio didn't deny the accusation told Satan _exactly_ how pissed he was. Well, if nothing else, at least he cared enough to get enrage on Shiemi's behalf. Progress!

* * *

Satan wasn't sure what exactly Yukio had said to Shiemi, but it was clear that something in their dynamic had changed. She stood a bit closer to him, talked much more animatedly to him, and didn't pay that Izumo bitch nearly as much attention before. He could hear them discussing a sort of plan that, though there were obvious roadblocks along the way.

Those roadblocks were, of course, Shiemi herself.

"Shiemi, go get a drink for me."

"Ah, um…" The girl paused, as if she were remembering a script, "I don't have any money for the machine!"

Izumo stared at her, her gaze slowly slipping back to where Yukio stood some ten feet away, a serene smile on his face.

"Oh, I guess I drained your funds, huh?" She said, the apology as fake as plastic, "Sorry, I didn't think you would have so little money on you. Here, there shouldn't be a problem anymore, right?"

Shiemi nearly fumbled the purse suddenly shoved into her hands. She stared at it, eyes rapidly darting back and forth between it and Izumo's expectant gaze. Her excuse gone, she caved, "Ah, um…Right! I'll be right back!"

Satan _looked_ at Yukio.

"It's a process."

Well, at least Shiemi seemed to have learned a little bit of spite, as she ended up using a good chunk of Izumo's money to buy drinks for the entire class.

"I'm sorry, I just thought that everyone would like a drink!"

"But that was _my_ money you used! I said buy me a drink, not give those idiots a free meal! You don't even talk to that puppet-creep in the back, why would you get _him_ something!?"

"I'm sorry, I was just trying to be polite…"

Or maybe not, if the way she profusely apologized was any indication unless she was just that good of an actor?

Shiemi slumped in her chair, face red and looked practically ready to burst, and Yukio seemed as if he was contemplating his entire plan, and possibly his life choices.

No, she really was just that innocent.

Satan found the entire display to be amusing enough that he patted the blonde's head as he walked past, sipping his drink. He grinned with far too many teeth when Izumo glared at him, nearly laughing when she looked away first. Intentional or not, she had managed to waste Izumo's money, which he personally thought was a thing worthy of praise.

* * *

It was after the first day of the so-called training camp that things started to change. Satan hadn't expected much actual training considering how weak most of the human children (sans Yukio) were. He was, unfortunately, proven right and found himself staring at a damn worksheet he had to fill out. It was mind-numbingly easy, though the idea of getting up at six in the fucking morning nearly caused a fight then and there. It was bad enough that the idiot trio was staying in _his_ dorm now and stinking up the place, but now he had to get up at the ass-crack of dawn?

Fuck that.

He didn't care what Kaoru had to drivel on about, so he left the moment he could without Yukio getting mad. Well, he would probably be irritated that he wasn't interested in 'socializing' with the idiot brigade, but tough luck. He had a bath to get before the leeches used up all the hot water.

* * *

Shiemi was happy that she would finally get some proper girl-time with her friends. Yukio was nice and unbelievably kind, but there were just some things that she couldn't talk about with him. Some of which was because he was a boy and others were, well…

W-Well, she needed to focus on making up with Izumo! Sure, Yukio had told her that she could reject any request of Izumo's that she didn't like, that she needed to be more assertive of her own thoughts because friends didn't use friends "like that", but she owed it to the twin-tailed girl this time after accidentally spending her money. It was an honest mistake, but, thankfully, Izumo didn't seem too mad about it once she calmed down and Shiemi paid her back.

It wasn't until they were outside the bathroom entrance that things changed.

"Shiemi, I that I need you to go get some fruit milk for Paku and I. Oh, but because you used my money, you'll have to use your own this time." Once again Izumo demanded a 'favor' from Shiemi. It would have been fine if that was all there was to it, but…"I also forgot my other bag in my room. Here are my keys, so go get it, ok?"

Paku frowned, "Izumo, don't you think that's a little much? Our dorm is on the other side of campus, and we have everything we need here…"

The plum-haired girl carelessly took her bag from Shiemi and stared at it thoughtfully for a second. She made a show of digging through it before huffing, "But I want some of my nicer things. Besides, she owes me for spending all my money earlier. It's only fair, don't you think?"

"But she already paid you back!"

"And?" Izumo drawled, letting the word drop like a stone, "It was stressful, so she owes me something for that at least. If she doesn't mind losing me as a friend, then she can just say no and not do it. Well?"

It was needlessly cruel to threaten Shiemi with a friendship that didn't even exist, but to Izumo, it was simply what was due. Fools were taken advantage of, used, and she had already been scorned, however unintentionally, by the blonde girl. Besides, she wasn't being half a cruel as she knew others could be. She could spread nasty rumors about her, trip her and pull at her pretty hair and mock her, or even outright ignore her existence until she felt like nothing but a shade. It would be so easy to break a girl who was so very desperate for love.

For some reason, Izumo couldn't help but hate her and the way others loved her, even with all her flaws.

The reply was small, but the answer was the inevitable, "I'll…I'll go get it."

"Shiemi!" Paku objected, but stopped when the other girl shook her head.

"It's fine, I made a mistake so I should make up for it…"

"We'll…" Something nasty and sticky was starting to stir in Paku's chest. Something that felt suspiciously like what she had felt years and years ago when she had been forced to decide which side she would stand on, "We'll wait for you, Shiemi."

Izumo made a disgusted face, "No, I didn't want to say it, but the idea of her seeing me naked creeps me out. So, it's best if she does these things while we wash up. Oh, but we can have 'girl-talk' after, alright?"

"Alright…"

Paku could only watch as the blonde girl trudged away, steps heavy and slow like the world was on her shoulders. She felt a strange sense of vertigo, like she wasn't where she was supposed to be. Like she was forced to watch a broken memory where the pieces didn't quite line up right.

Her chest hurt, and yet, beside her, Izumo sneered in a strangely familiar way.

And she climbed down the stairs, Shiemi decided that sound carried really well in the old dorms. So well, in fact, that she was sure that Izumo hadn't meant for her to hear her scoff after her and she descended the steps.

"Pft. 'Girl-talk', as if."

In fact, Shiemi decided that she hadn't heard anything at all.

* * *

Yukio was the first to notice Shiemi slowly making her way towards the door. He also instantly knew that something was wrong. Her posture, her blank expression, her very existence was wrong, "Shiemi, what are you doing down here?"

Shiemi was wilting, and he had a feeling that he knew why.

Shima perked up at that. Ever since the teacher had left, he had done little else but fantasize about certain actives, "Yeah, I thought you and the girls were gonna go have a bath scene together?"

"How tasteless can you be…" Konekomaru muttered, not bothering to look up from his notes.

"Don't you try and lie that you weren't imagining it too!"

Yukio ignored them, feeling something cold grip his heart when Shiemi stepped past him without even lifting her head. Even when he grabbed her shoulder to stop her, she refused to look at him, slouched over and practically shriveling and dying before his very eyes, "Shiemi, what happened?"

"I have to go get Izumo's bag for her."

Clod turned to hot and burst into flames, and Yukio felt a spike of rage so hot he felt light-headed. It made sense that Izumo wouldn't suddenly decide to play nice, but just what could have happened in such a short amount of time? He hadn't heard shouting or fighting, but Shiemi seemed so defeated and so very small.

It made he want to kill-

Yukio let go of Shiemi's shoulder. She slowly trudged away, dragging her feet with every step.

Everything felt far away and distant compared to the ringing in his ears, but he had enough common sense to realize that wandering out, alone, so late at night was a bad idea, "Kuro, keep an eye on Shiemi, ok?"

The demonic cat yawned from where he had curled by the table, but stood up and padded after the girl after mewling at Yukio. He was pretty sure Kuro was annoyed at being given such a mundane task but it was hard to think over the calm he had forced over himself.

"You're really just going to let her go?" Someone said, but he really wasn't sure who.

"I think she needs some time to process what happened. I tried telling her Izumo was just using her, but she didn't want to believe me. I think…I think she understands that now. She needs to decide what to do next, but it has to be her decision." Yukio explained though he didn't care if the others actually bought it or not. He must have looked rather heartless, sitting down and immediately burying his nose in a book, but that didn't matter. It didn't matter that he probably should go after her like his life was a sappy movie, because he had studying to do.

It had nothing to do with the fact that Yukio wasn't sure he could control himself right now. Nothing at all with the tiny and dark urges he felt rising within him, that made it all too easy to empathize with Rin's anger and rage.

It was a welcome distraction when his brother strode into the room a few minutes later, loudly demanding he needed a recently returned Kuro to help him find a strange smell.

* * *

Shiemi had taken her time getting the things Izumo requested. It wasn't because she was sad, no, she just respected that her friend wasn't comfortable being naked around her! Shiemi wasn't entirely comfortable with the idea either, so it was fine, really!

It was fine.

So, she took her time getting the bag. And the bag was rather heavy, so of course ,she needed to take a break on her way back. She might have spent a little time curled up on a bench, but that was only because Kuro had decided to follow her. Sure, she sat down to…to rest, but then he had jumped up and started demanding attention, so of course ,she had to stay there for several minutes to pet him. At least until he finally seemed to get impatient and very clearly guided her back to the dorm with little calls and flicks of his split tail. He was her little guide, though it seemed his duty ended once she returned to the dorm, for he almost instantly went to sit on a pile of discarded papers. She didn't dare look at Yukio and see his disappointment.

She tried to keep a tight grip on the small warmth she had felt bubbling in her chest from the entire encounter with Kuro, but it faded the moment she reached the bathroom entrance. It washed out of her like paints in the wake of icy water, leaving only cold grey.

"I forgot the fruit milk…" Shiemi realized. But it was too late to change anything, for Izumo stormed out at that very moment, a bit of water clinging to her long hair serving as proof that she really had taken a bath. Without Shiemi. She clearly hadn't need anything that was in the bag either.

That was fine.

"Izumo…"

The plum-haired girl snatched the bag out of Shiemi's hands with a snarl. She sneered at the blonde's wide-eyed shock, "There's still plenty of hot water left if you two want to enjoy your baths together now."

It really wasn't fine.

' _You two'_? Shiemi wondered, and realized that Izumo had already left, stomping her way up the stairs, "Wait, I…"

"Let her go for now, Shiemi." A strained voice, Paku, muttered, barely audible. Shiemi gasped at her appearance- still in her uniform but red-faced and with dried tears streaking her face. The brunette girl scrubbed her face when she noticed the staring, "I don't…I don't really want to see her right now."

Suddenly Shiemi's own distress felt small and petty, "What's wrong? What happened?" she asked as she followed Paku back into the bathroom. The benches had been cleared out by someone some time ago, but the two girls made themselves comfortable next to the lockers.

"Izumo and I…had a fight." Paku started after a terribly long time of nothing but silences punctuated with sniffling, "I'm so sorry for what happened, Shiemi, I should have spoken up earlier instead of just letting her do what she wants. I should have said something, but I couldn't because I was afraid of what she would say."

Shiemi didn't understand people at all. She had grown up with little more than her rather small family and their garden. The customers didn't count since she hardly ever talked to them, and she had struggled to make any friends. And so she had no idea how Paku, consumed by Izumo's shadow but always nice in her own way, could be so obviously hurt and still apologize to Shiemi. The brunette had fought her friend – something Shiemi couldn't even imagine doing – all for her sake.

She didn't understand why others were so kind to her.

But she knew how it felt to cry alone, and so she wrapped her arms around Paku, letting her tremble against her, "That's fine, you've done more than I think I deserve. I understand not wanting to make your friend mad, because friends are precious."

Paku let out a laugh that sounded more like a wretched sob, but it was so genuine that it made Shiemi smile anyway. After another moment, she pulled away, wiping her eyes, "You really are such a nice person, Shiemi. But that's not entirely it. I've always known that Izumo isn't the easiest person to get along with, but I wanted to do my best to make sure she wasn't alone and turned into an actually bad person." Paku said, voice strained with just a tiny tremble, "Because of that, I think I've overlooked a lot of things that she's done. She's…she's changed over the years, and I just don't know why. She's always been able to see demons, but one day-"

Shiemi didn't understand people, but she was less surprised than she should have been when Rin boldly strode into the girl's bathroom without a hint of shame. If anything, he seemed to be judging them for their place on the floor, a single brow raised in question like he wasn't being the strange one here, "Hey, do you two smell anything weird? I swear it was coming from here, but now it's gone."

"R-R-Rin!" Shiemi squeaked, tumbling over when Paku shoved the blonde behind her and shot to her feet. It was clear she had been crying just a few minutes ago, but, with sheer stubbornness born from embarrassment, she met Rin's eyes and loudly declared her indignation for all to hear, "This is the girl's bathroom, you aren't supposed to be here! Get out!"

The hallway erupted into noise.

"Whoa, he just went in!"

"I knew someone was in there!"

"Do you think he was smelling perfume or something…?"

Heedless of all common sense and decency, Rin just shrugged, "You two are clothed so what does it matter? Anyway, I'm trying to find a weird smell, so, Kuro, do you smell anything in-whoa!"

Rin yelped, yanked back into the hallway by his collar like an unruly dog. Yukio's voice echoed from the hallway a few moments later, punctuated with what sounded suspiciously like a person shouting while their mouth was covered.

"I am deeply sorry for my brother, he will be punished."

A shriek that reached an impressively high octave considering that Paku was pretty sure it was just boys outside rang out, "Oh my God, he _licked_ _my hand._ "

"I hope you die slowly when all that damn dye soaks into your pea-sized brain, Ryuji!"

"At least he didn't, I don't know, bite you?"

"Rin, you can't just barge in like that! Do even understand the concept of privacy or common decency? Have you…"

Shiemi and Paku exchanged bewildered looks. After a moment, it was just too much. The drama, the fights, the bickering and absurdity…they burst out laughing, completely drowning out Yukio's fading rant and Rin's squawking.

Because of that, not a single person noticed Kuro dart in and start clawing at the wall, meowing loudly.

" _Rin, I smell a demon! It's gone now, but it was here, I know it! Rin! Rin?"_

* * *

"You aren't usually one to fail your assignments, Mr. Neuhaus." Mephisto said in way of greeting the moment the Tamer stepped into his office to report. It hadn't been twenty minutes since his botched mission, but of course, the demon already knew.

He also probably already knew the details, but he had an obligation to report anyway, "Things didn't go as planned. Rin Okumura almost instantly knew a demon was nearby even if he didn't realize exactly what he was detecting. He started trying to get into the ceiling to investigate almost instantly and would have found my familiar if I hadn't acted. Based on what I've heard about the boy, a single Naberius wouldn't have been any issue for him."

"Correct, and he probably would try to kill you if he suspected you were even the tiniest threat to his precious brother!" Mephisto chimed in cheerfully, as if death was just a delightful little topic to him to discuss over tea. It probably was to such a creature, "It would be a shame to replace you so early..."

Somehow, Igor managed to maintain his composure. He hadn't been told exactly how dangerous or aggressive the boy was, and while some might have though Mephisto was exaggerating, he could see the truth behind that coy smile. He knew he wasn't well loved or seen as anything more than a piece in an overly elaborate game, but he didn't like being set up to be eliminated.

"Well, never mind the details, we'll just have to eliminate the weakest link a different day. Don't give me that look, I'll be sure to handle the troublemaker on my own," The demon paused, thoughtful for a second, "Oh, but how exactly did Mr. Okumura discover you? I would have thought you knew a thing or two about secrecy."

"He smelled it."

Mephisto laughed.

* * *

 **In hindsight, the Naberius attack on Izumo and Paku makes absolutely no sense. It isn't an attack on Rin, so you can't say it's part of Igor's orders. Sure, Rin does get involved eventually, but it seems to be a direct attack on the girls, which doesn't add up unless you look at it in the context of trying to get rid of Paku and/or Izumo. Only one of these makes sense given their abilities.**


	32. The First Trial

Chapter 31: The First Trial

 **The 'heart' is a fickle thing.**

* * *

"What are you doing," Yukio said in leu of greeting that morning.

It was painfully obvious exactly what his brother was doing, but a small part of him hoped that if he asked, somehow the answer would change. But no, nothing changes, and the older teen only blinked at him from where he sat, a glowing orb of blue held in his hands. It almost looked like a will-o'-wisp, but the color is too rich, the eerie blue light too powerful.

It was not the first time Yukio had seen that fire, but he had never seen it as anything more than a flicker. This was strong and purposeful, filled with strength that frightened a primal part of him.

Satan shrugged, palming the fire into one hand as if it were a physical thing and not just pure power and will. The seal on his powers was riddled with holes and shot to hell to the point that he was sure he had a month left, maybe two if he was careful. Yukio knew about the fire, but he hadn't really seen it.

So, it was time to properly introduce it. Baby steps, as Yuri would say, because too much at once was a shock and led to mistakes and regret, "Practicing. Come here and take look."

"Rin, that is literal hellfire," Yukio announced, as if his brother wouldn't be acutely aware of that fact and continue to not care.

"And it's _mine_ ," Satan insisted sharply, before Yukio's thoughts could tread down any troublesome roads, "So I don't see what's the damn problem. Besides, I can control it. Do you want to hold it?"

The small ember was held just inches from Yukio's nose like an offering, equally blue eyes peering at him expectantly.

"That's…"

"It won't burn you, I won't let it." He would sooner cut off his own tail than let that happen. Yukio looked conflicted, so, as usual, Satan took the initiative and grabbed one of Yukio's hands with his own free one and turned it up. And, without a word of warning, plopped the ebbing flame into it, "Look. See?"

Yukio did not flinch like he knew he should when a ball of literal hellfire was carelessly dropped into his hand. He caught it reflexively and didn't cry out in pain or suddenly feel his hand being burned away to the bone. No, instead he gripped the fire a bit tighter and watched the blue crackle and snap but do nothing to harm him. It was warm and felt like a small sun, and yet was simultaneously lighter than air itself. It flickered in his cupped hands, sputtering weakly and tickled like a butterfly's wings. Ahead of him and unnoticed, Satan made a face as he concentrated, and suddenly the weak flame was bright and heavy with power. Yukio flinched at the sudden change, very nearly dropped the azure fire, but Satan cooed comforting words and refocused his child's grip on the flames.

Hot, so hot that the heat raced up Yukio's arms and sank deep into his chest, slowly dripping down into his bones and through his nerves. It was hot, just skirting the line of too-hot, but somehow, it wasn't uncomfortable at all. It felt like he had submerged himself into a bath, with heat that nestled under his skin and relaxed his muscles but didn't burn.

The flame flickered and pulsed like a tiny heartbeat, just a half-moment off from mirroring his own.

"I told you it would be fine. It only burns what I want," A half-lie, but one Yukio would hopefully never know. Assiah was a terribly beautiful tinderbox after all, "And I would _never_ want to burn you, Yukio."

Yukio swallowed and forced himself to concentrate. He didn't let himself think about just how enthralled he had been with the flames.

"How long have you been practicing then? This can't be good for the seal."

Seal-this, seal-that, it all came back to that, didn't it? It was as much as a blessing as it was a pain to tiptoe around lest he break the terribly fragile thing, "That's a secret. And the seal is going to fail or get broken one day anyway, so I might as well know what I'm doing, right?"

Yukio stared at him with an expression that he was clearly thinking about something too much. It was enough to make unease uncurl itself in Satan's gut, but before anything more than that, the teen adjusted his glasses and declared:

"You aren't allowed to burn your homework or anything else with this, Rin."

Satan snorted and firmly pretended he hadn't already done that exact thing, "Oh no, I've been found out." He deadpanned instead.

"I'm serious, Rin." Yukio lectured, hand holding blue fire casually now and looking as serious as could be, "Using hellfire to burn paper is a serious violation of ethics, rules, and all things good and moral."

It took an embarrassingly long time for Satan to realize that Yukio was, at least partially, joking, "When did you become such a smartass, huh?"

"You're the worst influence. Now come on." Yukio plopped the tiny fire back into his twin's hands, having no idea what to do with it, or how (if at all) he could extinguish the flames, "Put out that fire. We have class to get to since you refused to get up for the review."

"Don't schedule it at fuck-you o'clock then!"

* * *

Satan knew that some petty teen drama bullshit had occurred last night. It was impossible to not notice just how pissed off the twin-tailed bitch was, nor the fact that her lackey had decided to start hanging around Shiemi's shadow instead. He knew all about backstabbing and betrayal, so it wasn't hard to realize that she had been abandoned, too insufferable and too weak for anyone to stand. It was just shameful that she couldn't even keep up her façade for class, and it might have been funny to watch it crumble if it wasn't, well, so pathetic. And irritating.

"Who even wants to be an Aria?!" Izumo shouted, flustered and willfully ignoring the way she disrupted class as she sneered at Ryuji, "They're completely defenseless while reciting, and have to rely on the rest of their party to protect them. They're nothing more than baggage!"

"What the hell was that…?!"

Satan rolled his eyes and, without even needing to stand up, easily cut through the mounting tension, "And what use is a Tamer who can't even summon?"

"What?" The plum-haired girl yelped, glaring fiercely at Satan, "I'll have you know that I'm the strongest Tamer here, with two foxes under my command!"

She really was trying too hard to look unshakable when it was a pointless effort. Honestly, did she think no one had noticed the way she had been sulking all day? A mask was only good until it slipped, and then it could never be put back on correctly, not when everyone had already seen what was under it. It was why Satan himself never bothered with them for any extended periods of time.

Her mask had slipped, and he could see the hesitation, the uncertainty in her eyes clearly now. He could almost see that weakness clinging to her, leaving her heart open and calling to a slumbering part of his soul.

Yes, she really was just ripe for the taking.

"And didn't I tell you that foxes have no sense of real loyalty?" Satan countered easily, "Look at you, trying to pick fights just so you can ignore your problems. Fucking pathetic! The moment you summon, they'll turn on you."

"Why you-!"

The response was weak, and Satan sighed at her stupidity.

"If you want to prove me wrong, then summon them right now. Don't count on me to save you though."

The teacher finally spoke up, tone harsh and annoyed, "That is quite enough, Mr. Okumura. There's no need to provoke your classmates."

Satan might have said more, but Yukio sharply elbowed him before his mouth could get him into trouble (again).

* * *

It turned out that Satan could not, in fact, stay out of trouble. It was near the middle of the second study session that Kaoru received a call. Satan hadn't been paying attention to anything for the past ten minutes, instead choosing to focus on teaching Kuro to catch paper balls mid-flight whenever the teacher wasn't looking his way. It was a simple and petty exercise in subtility, but whatever, he was sick of studying that he wouldn't even use.

He probably should have been paying more attention, because suddenly he was being pulled off the floor by Igor who had apparently shown up at some point.

"Don't touch me you creep!" Satan hissed, shaking off the too-tight grip easily.

"Your presence has been requested by the headmaster," Igor said, his normally perfect deadpan wavering with just a hint of irritation.

"And what the hell does he want me for?" Really, what the hell did Samael want now, and why couldn't he just come himself? No wait, that would put him near Yukio, and he didn't want _that_ , so-

"I believe it has something to do with a certain incident with one 'Reiji Shiratori', if that jogs your memory?"

Satan knew exactly what had occurred involving _that_ particularly nasty little shit, but he was careful and had covered his tracks, "…You can't prove anything."

"The security cameras would argue otherwise."

Damn it all.

Yukio stood and stalked over to his twin, "Rin. _What_ did you do?"

" _I_ didn't start shit."

" _That_ wasn't my question."

"Ahem." Igor interrupted, pulling the shorter back to his side and away from the seething younger brother, "You can interrogate your brother after the headmaster has dealt with him."

Satan groaned. Fantastic, he had to deal with Samael being a smug shit to him and he couldn't do anything about it without raising questions he couldn't answer. He really missed being able to slap the shit out of whoever annoyed him without consequence, "Oh, not that fucking-"

"Watch your tongue before something happens to it." Igor snapped, pushed the teen towards the doorway.

"I hear you can bite through fingers like carrots. Which is total bullshit, mind you, but it sure is _interesting, isn't it_?" Satan's grin was all teeth and he nearly laughed when the man's perpetual frown deepened. Behind him, Kuro followed, asking inane questions such as _"What are carrots?"_ and _"Are we going to fight the eyepatch man?"_.

Satan really didn't anyone goading him, however, unintentionally, into fighting Igor. Especially not with all the cameras that were apparently around.

* * *

The rest of the class watched the exchange, some disturbed, some (Yukio) exasperated. It was a relief when the teachers left to escort Rin away, his familiar darting after their heels like an excited child.

In the stretching silence, Bon plainly said, "I know I've said this before, but your brother is a freak."

"He's also by far the strongest person in our class and manages to perform at least above average on virtually every exam." Yukio responded coolly, not even bothering to defend Rin when he was irritated with him, "Think of him what you want, but he's one day going to be your strongest ally on the field, Bon."

A non-distinct grunt was the only response Yukio got. At least it wasn't shouting.

Shima snapped the book he hadn't been reading for the past ten minutes closed, "I think you all are missing the _real_ point here: just what kind of trouble do you think Rin got up to this time?"

"A fight."

"Ah, boo, that's boring. He's always fighting, so what makes this special?"

Knives, broken bones, or just a rich brat's bruised ego, were all things Yukio didn't say. Instead, "He's always fighting, so why should I expect anything different? I'm just irritated since he promised he would at least try and behave…"

It was about this time that the lights flickered out. Naturally, everyone froze at the sudden darkness, a hush falling over them for a half second before chaos exploded. Yukio ignored the crashing and yelps as his classmates panicked and tripped over themselves in the sudden darkness, instead letting his own eyes adjust. It was still surprisingly bright for a blackout, and it took a moment for him to realize where the light was coming from: every other building and light outside was still working.

He had no reason to assume that the older building had suddenly lost power due a to failed circuit or the like, but, despite all logic, Yukio was suddenly very warry.

He didn't fail to notice that the windows wouldn't budge when he tried to open one.

Someone -Shima- had managed to use their phone as a light, and one by one the others followed suit. Yukio could distantly hear the other chattering about blackouts, but he shook his head, scanning outside, "No, it can't be that. The other buildings still have power."

Bon frowned, easily catching the unease in Yukio's voice, "So what's that mean then?"

He was suddenly acutely aware that both teachers were gone, that Rin and Kuro had been taken away only a few minutes before, and with those pieces, the puzzle was quickly coming together. But instead, he lied, "I don't know, but I don't like it. Everyone should be ready for the worst-case scenario. Shiemi, Izumo, be ready to summon at a moment's notice."

"I…I already have Nii ready, Yukio!" Shiemi announced, a little nervous hitch in her voice. The Greenman squeaked from where it sat on her head.

Izumo stood suddenly, glaring at Yukio, "Hold on, who put you in charge? And what makes you think that something bad is going to happen anyway?"

Yukio let his eyes scan the room, trying to figure out what was going to happen next. There had to be something more if this really was a test, and he was amazed the others hadn't at least suspected something, "Don't you think that it's a little suspicious that only we've lost power, and right when our teacher has left?"

"A trap…?" Paku asked, her eyes wide.

"But why?"

"Because someone probably... Everyone, be quiet." Yukio hissed. It could be a test, or their lives could very well be in danger. Until he knew one way or the other, he had to treat everything as if it were as real as it appeared.

It was about that time that Yukio heard a strange moaning-growl echo from outside the door, far too close for comfort. Bon tensed, eyes clearly darting around and looking for a weapon, Shima visibly shivered, Konekomaru took a step back, and Paku let out an audible whimper. Izumo, however, took a step boldly forward, a summoning paper in hand, but…but she was shaking just the tiniest bit, her eyes darting to the paper, clearly unsure of herself now, when it mattered the most.

Whether or not Rin had shaken her or if this was purely a result of her fight last night didn't matter. The reasons didn't matter now, only the results.

"Don't summon anything you can't handle, Izumo." He hissed at her. The last thing they needed was friendly fire. He risked a glance away from the door and to the window. It had been locked through a means he couldn't identify, but maybe they could break it and escape, though he doubted it. He had been around Rin enough to know that decent windows were not, in fact, as breakable as movies liked to portray.

"I can do this, I'm not weak!" She shouted angrily.

Too loud, and suddenly something threw its weight against the door, cracking it ominously. More noises, more enemies, and Yukio didn't even waste time cursing his luck. Of course, Rin had been taken away along with Kuro, of course for whatever terrible test was planned for them their strongest fighters had to be taken away. But, once again, Yukio himself had been underestimated, his brother such a threat that no one ever considered the meek little boy with glasses.

It was their mistake.

"Get ready, we're…"

Yukio stopped, feeling his blood run cold. Even when the demon finally broke through the wall, he found his thoughts foggy with sudden, all-consuming panic. He had immediately gone for the hidden gun he had started carrying on his person at all times ever since the Astaroth incident, glad for once that Rin was such a delinquent that he could teach him how to hide even a pistol.

Except…

Except, his gun was missing its magazine.

* * *

Satan walked into Samael's office just in time to see the gaudy demon slip a black brick-shaped object in his desk drawer. His entire demeanor screamed suspicious to Satan, but then again, he was hard-pressed to think of a time when Samael _wasn't_ acting shady, so the king of demons ignored the rising urge he felt to cloak himself protectively in flames to shield himself from any magic. Instead, he stalked towards the great oak desk and stood in defiance even as a chair was offered to him. He wished he hadn't been forced to leave Kuro outside.

"Come now, Rin, sit down and relax for a moment. We have much to talk about," Samael offered, his voice as pleasant as someone like he could make it. It didn't fit his sharp eyes at all.

"I haven't done shit," Satan stated and did nothing else. He wasn't in any particular rush to go back to the dorm and do more pointless work, but he didn't want to stay here any longer than he specifically had to.

"Now, now, do you really think I care about what these entitled brats at this school want? If it were up to them you would have been expelled the very first week, and then where would either of us be?" Samael chuckled, though the laughter faded quickly when Satan failed to join in and just continued to stare at him, "No, I just felt that we needed to have a proper chat about your future. It's been what? Two, three years since we talked?"

"What do you want?" The demon said to the other, and nearly growled when he saw a certain smugness cross Samael's eyes when he opened his mouth to talk, "And before you go and try and confuse me, I haven't forgotten our little talk a few years ago, so you can skip that part."

Samael's greatest weapon was not his powerful magic or crafting mind, but instead his ability to lead men to their dooms with nothing but words. If he was given a single millimeter, he would take an entire country with little more than a speech and his brash confidence. It had been infuriating to accept the fact that one of his children was, without question, _smarter_ than he could ever hope to be, but eventually, Satan had learned and adapted, as he did to all things.

If Samael ruled through words and twisting your very thoughts against you, then Satan just had to tear through his narratives with reckless abandon.

Green eyes, sharper than any blade, peered at the teen in question with obvious curiosity, trying to pick him apart with just a glance. Satan fearlessly met the prying gaze, daring Samael to even try and figure the utter madness that Satan had made real.

"If you remember it so well, then you should know that your dear brother interrupted our conversation with that little temper tantrum of his. Just because he didn't like the reality of your role to play, didn't mean he had to get violent like that."

"You pretty much outright said you wanted me to be your puppet. You're lucky he got mad before I did." Well, it more went that Satan was lucky that Yukio had raised such a fuss that no one had noticed him trying to not burst into hysteric laughter at the thought of the son who hated him the most putting him back on his throne. But semantics.

"Ah yes, I wouldn't want to face the little prince's wrath, now would I?" Samael asked, sarcasm clear.

Satan ignored the jab, instead feeling a bit offended about what had just been implied, "Yukio is royalty too."

"And he's painfully human," Samael lazily flicked a finger as he spoke, and suddenly a chair bashed into the back of Satan's knees, forcing him to fall back and scooting him snugly up to the table before he could react. The Demon King ignored the teen's angry cursing and continued, languidly, "but that doesn't matter to you, does it? No, it would be more accurate to say that nothing matters to you _except_ your precious Yukio."

Satan stopped his struggling at the way Samael's voice dropped dangerously low with curiosity and venom. He couldn't fully hide his reaction, but sudden fear gave his mind a sharp edge, and so he managed to ask with deceiving calm, "What are you implying, Samael?"

"I would rather you call me Mephisto. It has a much nicer ring to it, doesn't it?"

Satan felt his anger flair at the casual discarding of the name he had been given and this time, he couldn't quite contain the growl, "Shut up and explain."

The pressure in the room suddenly seemed to magnify from the pure murderous intent. It was just an illusion, but it still threatened to steal Satan's breath away from his weak human shell. There was no discernable change in Samael's tone that any human would notice, but to a fellow demon, he might as well have been seething, "Maybe you should stop assuming that you're in any position to demand anything from me, _child_."

The challenge had been issued and while most humans would freeze when faced with such an overwhelming force, Satan could feel nothing but white-hot anger that _his_ child had the gall to think he was better than him. He had beaten Samael a dozen, no, a hundred times before, and he would do it just as easily as he always did. Such an ungrateful, arrogant _brat_ to challenge his father who had done so, _so,_ much for him. He had kept other demons from killing him while he was young and weak, given him every resource he could find, and, most of all, suffered for a near eternity in Samael's place just to save his miserable life from the eld-

Satan could not defeat Samael as he was, not without abandoning the false life he had made for himself. And so, he controlled his anger and did nothing but silently seethe.

Apparently, his obvious helpless frustration was amusing enough to cool Samael's temper. The challenge lessened to something manageable, and the Demon King relaxed, leaning back in his overly plush chair with a content smile, "You're lucky that I find your temper to be so cute in its futility. Plenty of our other brothers would have already killed you."

"They can _try_." They could try all they wanted, but the moment anyone decided that killing family was fair game was the moment Satan would step in and remind his idiot sons that the very few ground rules he laid were to be _respected_.

"Determined like a human, I approve!" There was a glint, hungry and cunning, and Satan knew that Samael's interest in him had grown to dangerous degrees, "But you were the one who said that you wanted me to get straight to the point, correct? Well, I have a simple question for you: Is Yukio your heart?"

All thoughts ceased, and he wasn't sure if it was shock, anger, fear, or just confusion.

His heart? But that didn't…

Satan must have voiced his confusion, for a grin nearly slip Samael's face in two, "If you're wondering, I don't mean your literal demon heart, like the blade you really should get in a habit of carrying around..." Green eyes peered accusingly at the spot over Satan's shoulder where the Kurikara should have been, "But never mind that. No, what I mean is something more metaphysical, and something so very human. Is Yukio your heart, your world, your everything? Is he the reason you wake, and the reason you continue to live?"

Hearts were something incredibly important to demons. Human hearts were little more than organs that pump their blood, and though their metaphorical hearts were where demons could latch onto and squirm into, it wasn't even somewhat the same. Demon's own, literal hearts, in contrast, held the very core of their beings. It was the cumulation of their existence, the absolute purest distillation of who they were, and without it, they would die.

It was the core of what a demon was, and yet…And yet, Satan himself…

"Why?" Was the only thing Satan could force himself to ask without exploding. Demon hearts were invaluable, yes, but human 'hearts' were something else entirely. They were the source of so much strength, so much pain, and drove them forward, so for Samael to identify Yukio as a metaphorical one, well…well, that wasn't exactly wrong.

And the most important thing was that human hearts, unlike demons, could _break_.

"Because a heart is a weakness!" Samael declared, pointing squarely at Satan's chest, "The heart is how humans are possessed by demons, and a weak heart is what ultimately killed Satan. He grew to love like a human, and so when that was taken from him, he couldn't survive!"

Ah, suddenly things made a lot more sense. A human heart was the source of love and often the reason humans would push to survive. It wasn't a pure cumulation of their being and was instead fickle, often at war with their own wants and identity. It was wretched and beautiful, a contradiction that drove many to madness.

Of course, it would only be seen as a liability to be exploited to a proper demon. Of course 'Rin' having a human heart so wholly invested into a single other's life was a problem for Samael.

"…You really can't understand love at all, can you?"

Love born from a weak heart relearning to connect with another was the only reason Satan had been able to grow to care about, well, _anything_ again. But no one but Yuri could be allowed to know just how deeply he had cared in the end. Not yet, at least. And so, he could only look at Samael, feeling just a bit of pity as he realized that he would truly never understand the feeling. But, a part of him was equally relieved, for so few demons could love that it would simply be better if none ever did.

Samael, ignorant of his father's musings, scoffed at the notion of love. He had seen exactly where that had gotten enough delusional demons, thank you very much, "Any demon who learns to love ultimately finds their own death at the end of that very same love. And that can't happen to you, Rin. You have a role to fulfill, so I can't have you break on me."

 _'_ _Threat'_ , Satan's mind screamed. A threat to Yukio, to his 'heart', "If you're threatening Yukio-!"

A hand held before him somehow stole the teen's voice, allowing Samael to speak, "You may think lowly of me, but I'm not stupid. Besides, you don't have to say anything to me, I can already tell that Yukio is your 'heart'." Magic or not, Satan shot to his feet, knocking the chair back and stabbing a knife into the hardwood in an obvious threat before the clattered even stopped. The King of Time, however, looked distinctly unimpressed at the display, "Oh, don't look at me like that, you look _far_ too much like a real demon there. I'm offering to help _protect_ your brother, Rin."

A deep breath in and Satan managed to steady himself, "How?"

"Your brother shows a lot of talent as both a Dragoon and a Doctor. One of these fields is quite dangerous and has many…work-related accidents." Samael began, smirking at the way Satan flinched, "However, Exorcists who are only Doctors usually say behind to prepare a field team and also heal any wounded who manage to make it back. Yes, some may go out into the field, but Yukio is quite promising, too valuable to risk I would say."

"Why are you offering this?" Nothing was free when it came to deals with the devil, after all.

"Yukio might be a talented Exorcist the order very much needs, but, ultimately, you are much more important," In some ways, it was foolish to admit just how much power the other party held, but not when it was Samael speaking. No, he knew exactly how much power a child of the blue fire had, but, ultimately, he had accumulated far more resources and had too much to offer to be ignored, "Therefore, I cannot have you _break_ if something were to ever happen to your dear younger brother. It would raise too much suspicion to hold him back after this test, but it's a simple thing to shuffle around his assignments. Well?"

Something nagged at the back of Satan's mind at that phrasing, but he ignored it as the low buzz of barely restrained anger, "And what do you want?"

"Your complete cooperation. While you've yet to break any serious rules, you've come close. I can instruct your teachers to ignore your terrible language, but behavior is another matter altogether," Samael informed, whimsy gone for something a bit more serious, "You will follow their rules to the letter, and I'll make sure Yukio is never in any more danger than he ever has to be."

"I'll obey unless it endangers Yukio." He could swallow his pride for that much, at least.

"Of course!" The King of Time chimed, nodding enthusiastically even at the sharp creak that resounded when the knife in his desk was pulled free. He watched the teen put away the knife rather skillfully, very aware that a certain demon blade was much longer and cumbersome and likely hard to eventually adapt to. Well, it wasn't like the sword would be the boy's main method of attacking anyway.

He made a show of checking a watch that hadn't been on his wrist a second ago, "Now, our agreement will go into effect in approximately…two minutes."

"Huh?" Too-blue eyes blinked in confusion, "Why then…What's happening? What did you do?"

"You're much too strong, so I decided that you didn't need to participate in the Authorization Exam with the others," Samael replied, idly wondering just how thoroughly the boy would have utterly destroyed the Naberiuses that had been used. It would have been hilariously easy for him considering his history (and wasn't dear Astaroth even more of a joke now, losing to a demon who hadn't even awakened properly?), but that defeated the purpose of the exam itself, "Don't worry, I'm confident that your brother is doing fine. I would have been notified if anyone was mutilated too badly!"

The chipper tone was a sharp contrast to the way Satan could feel his blood freeze, an icy jolt of panic shooting down his spine. He knew Yukio could take care of himself, he had trained him after all, but that didn't mean he should be fighting demons all on his own just yet! The rest of the class was a bunch of deadweights and jokes compared to Yukio, they would get him hurt as he tried to protect them!

Satan didn't remember running to the door, but he very much did realize it wasn't opening. He whirled around and snarled, "Let me out before I feed you your own intestines!"

Samael sighed, "Do you really think I don't have precautions in place? There's plenty of senior Exorcists monitoring the exam, don't you worry your little head about it! Ah, stop that, it won't work and you should know better," The demon tutted and nodded in approval when the other finally stopped trying to kick the door down. That glare really was something straight off of father's face to the point of being eerie, but he ignored his own unease to continue, "Just answer me this one question, and I'll let you run into your dear brother's arms. Human hearts are fickle things, and Yukio might grow to hate you one day. Could you even survive something like that?"

That was…tricky. It was something Satan didn't even want to consider, something he _knew_ would break him if it happened. He would break into tiny shards of misery and self-loathing, would want nothing more than to curl back into numb apathy, and would probably curse ever rediscovering his heart…

"As long as he's happy and safe…"

…But…but he would survive. He might not be happy, he might need someone to put him back together or else he would fall back into his old ways, but he would live. If Gehenna and all the monsters it bore couldn't destroy him, then that wouldn't be the end of him. He wouldn't embrace death after struggling for so long.

"Then that's all that I have any right to demand."

…Right?

The door clicked open and Satan ran away from his thoughts, not even hearing whatever drivel Samael had to say.

* * *

 **When you only want to write one part of a scene, but somehow a 3k conversation springs up around it.**

 **I'd like to throw out a quick reminder that Satan's perspective on things is not 100% accurate, nor has ever really been. Just because he assumes something doesn't mean it's true, but it's in his nature to be judgmental.**

 **And no, this story isn't going to turn into Izumo-bashing, or any character bashing for that matter.**


End file.
